Idaho Road Signs Practice Test
Sharpen the skill the Class D Knowledge Test leans on most: 25 questions on road sign shapes, colors, and meanings, each explained in plain English. The real DMV Class D Knowledge Test has 40 questions, and you need 34 correct (85%) to pass.
Tap an answer. The explanation opens so you can learn it, then go on. Keyboard: A–D or 1–4 to answer, then Enter or Space.
Question 1 of 25
1. A center lane is bordered on each side by a solid yellow line with a broken yellow line inside it, and white left-turn arrows are painted for both directions. How may you use this lane?
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Correct answer: A. A two-way left-turn lane is shared by both directions for left turns only. Enter just before your turn, watch for opposing drivers using the same lane, and never travel or pass in it. Turn, do not cruise.
2. A round yellow sign with a black X and the letters RR is posted well before a crossing. What does that advance sign tell you?
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Correct answer: A. The circular railroad advance sign gives you time to slow, scan both ways, and be ready to stop. Do not stop on the tracks. Circle plus X means rails are coming; the crossbuck at the tracks is the actual yield-to-train sign.
3. You are driving past a school crossing just as classes let out. What must you be prepared to do?
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Correct answer: C. Near school crossings you must slow to any posted school speed and stop whenever children or crossing guards are in the crosswalk. Kids are small, quick, and unpredictable, so extra caution is required. Expect the unexpected wherever students gather.
4. A white sign with a green arrow and the word ONLY is mounted beside a traffic signal. When may you move in that direction?
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Correct answer: B. A signal-mounted green arrow with ONLY ties that movement to the arrow indication. Go that way when the arrow is on and the path is clear; otherwise wait. Arrows assign time as well as direction.
5. At the top of a ramp you see a square sign with a red circle and a white horizontal bar reading DO NOT ENTER. What does it mean?
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Correct answer: A. DO NOT ENTER marks a roadway where traffic flows toward you, such as an exit ramp or one-way street. Entering it risks a head-on crash. If you have already turned in and see WRONG WAY, pull over and turn around safely.
6. You see a yellow diamond sign showing an arrow that bends left, then right, then left again. What does this sign tell you about the road ahead?
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Correct answer: C. A winding road sign warns of three or more curves in a row, while a single-bend arrow marks just one curve. Knowing the difference helps you hold a safe speed. Think: a wiggly arrow means the wiggles keep coming.
7. A sign at an intersection shows a left-curving arrow inside a red circle with a diagonal slash. What must you do there?
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Correct answer: D. A slashed left arrow forbids left turns at that intersection, often because turning across oncoming traffic there causes crashes or blocks flow. Plan another route, such as continuing straight and circling the block. The slash cancels only the movement shown.
8. You see a white square sign showing a curved U-shaped arrow inside a red circle with a slash through it. What is prohibited?
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Correct answer: B. The slashed U-arrow bans U-turns at that location, usually because oncoming drivers cannot see you turn around in time. Continue to a spot where reversing direction is legal and safe. Red circle plus slash means the pictured move is forbidden.
9. You are in the right lane when you see a yellow diamond sign showing the right lane narrowing into the left lane. What should you do?
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Correct answer: B. A lane-ends sign warns your lane will disappear, so signal, match the other lane's speed, and merge before the pavement runs out. Drivers in the ending lane must yield to through traffic. Early, smooth merges prevent the last-second squeeze.
10. You stop at a red light planning to turn right, and a white sign beside the signal reads NO TURN ON RED. What does the sign change?
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Correct answer: A. Many places allow a right turn on red after a complete stop, but a NO TURN ON RED sign removes that option. It appears where crosswalks or sight lines make red-light turns risky. When posted, red simply means wait.
11. A wide white bar is painted across your lane just before an intersection with a stop sign. Where must you stop?
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Correct answer: D. A stop line marks the exact place to stop: bring your vehicle to a halt before the bar, not on or past it. It keeps you clear of crosswalks and cross traffic. The bar is the boundary.
12. A white rectangular sign reads WRONG WAY. You have just entered a ramp. What is the safest first move?
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Correct answer: C. WRONG WAY means you are driving toward oncoming traffic. Stop without blocking others if you can, then leave the roadway the way you came or wait for help. Continuing forward is how head-on crashes start.
13. Orange signs, cones, and barrels suddenly appear along the highway. What does the color orange tell you?
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Correct answer: B. Orange is reserved for temporary traffic control, meaning construction and maintenance zones. Workers, machines, and lane shifts may appear with little warning, so slow down and stay alert. When you see orange, think people at work.
14. A yellow diamond shows a truck tipping on a curved arrow. What should you do before the curve?
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Correct answer: B. The tipping-truck symbol marks a curve or ramp with a recommended lower speed for high-center vehicles — and a wise lower speed for everyone. Slow before you enter the curve, not in the middle of it.
15. You plan to leave the freeway at exit 12. How will you know which ramp is yours?
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Correct answer: B. Freeway exits carry green guide signs topped with a numbered exit panel, and the number usually matches the nearest milepost. Match the posted number to your planned exit, then move into the exit lane early.
16. You see a red-and-white triangular sign reading YIELD as you approach a traffic circle. What should you do?
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Correct answer: B. A yield sign tells you to slow down, check for traffic with the right-of-way, and stop only when necessary to let it pass. It keeps merges smooth without forcing pointless stops. Think of yield as give way, not a full stop every time.
17. In a work zone, an orange sign warns of a flagger ahead. The flagger signals you to stop, even though the traffic light beyond is green. What should you do?
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Correct answer: C. Flaggers control traffic through work zones, and you must obey their directions even when they conflict with posted signs or signals. They can see hazards you cannot. Remember: in a work zone, the person outranks the light.
18. A solid white line, instead of a broken one, separates your lane from the next lane going the same way. What is it telling you?
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Correct answer: A. A solid white line between same-direction lanes discourages lane changes, and it appears where drifting is risky, such as near intersections and ramps. The firmer the line looks, the firmer the message: hold your lane.
19. Which MUTCD warning-sign group includes the Deer sign W11-3?
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Correct answer: A. Official MUTCD 2009 Part 2C lists Non-Vehicular 2C.50, 51 Pedestrian, Deer, Cattle, Snowmobile, Equestrian, Wheelchair, Large Animals, Playground as W11-2,3 and related signs. Testers invent leftover dusk-group folklore. Learn that official wording, then answer the knowledge test from those words.
20. You are low on fuel on a long highway drive. Signs of which color point you to services such as gas, food, lodging, and hospitals?
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Correct answer: B. Blue signs mark motorist services, including fuel, food, lodging, rest areas, and hospitals. They let travelers plan a stop before leaving the highway. When your body or your car needs something, look for blue.
21. A yellow diamond sign shows a truck tilted nose-down on a black slope. You are about to descend a long, steep grade. What is the proper technique?
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Correct answer: C. On a steep downgrade, shift to a lower gear before descending so engine braking holds your speed, and use the brakes sparingly. Constant braking overheats the pads until they fade and fail. Gears save brakes; brakes alone can quit.
22. You see a yellow pennant-shaped sign on the left side of your lane that reads NO PASSING ZONE. What should you do?
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Correct answer: B. The pennant is the only sign that points to the left, marking the start of a no-passing zone. Do not pull out to pass until you see a regular passing-allowed marking. Left-side pennant means stay put.
23. Wide white stripes cross the pavement ahead, marking a crosswalk. What do these markings require of you as a driver?
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Correct answer: C. Crosswalk stripes show where pedestrians are expected to cross, and drivers must yield to people within them. You stop only when someone is crossing or a sign or signal requires it. Painted stripes mean feet ahead.
24. Leaving a one-way street, you see a yellow diamond sign with two vertical arrows pointing in opposite directions. What is it warning you about?
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Correct answer: A. The two-way traffic sign warns that the one-way section is ending and vehicles will now come toward you. Keep to the right and use extra care when passing. Two opposite arrows mean the road now flows both ways.
25. Which shape is used only for yield signs, so you can recognize the sign even when you cannot read its face?
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Correct answer: D. Only yield signs use the downward-pointing triangle, just as only stop signs use the octagon. Unique shapes let drivers react from the outline alone in fog or darkness. Picture the point aiming down, telling you to back off and give way.
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