279. In your mirror you see a car approaching from the rear. The next time you check your mirror you don't see the car. To change lanes you should:
Detailed Explanation
The correct answer is "Wait until you are sure the car isn't in your blind spot.". This is based on federal CDL regulations and safety standards.
Correct Answer: Wait until you are sure the car isn't in your blind spot.
Why This Matters on the CDL Test
This is a vehicle-control question. Practice connecting the rule to the driving action: checking mirrors, managing space, planning turns, and avoiding sudden movements are all tested because they prevent crashes in real traffic.
How to Remember It
Say the rule in your own words, then explain why the wrong answers are unsafe or incomplete. That habit makes similar General Knowledge questions easier when the exam changes the wording.
Answer Review
Choose "Wait until you are sure the car isn't in your blind spot." because this answer matches the safe CDL action for space management and mirror checks. On the knowledge test, the safest answer is usually the one that protects space, control, visibility, legal compliance, or inspection accuracy before the vehicle is put at risk.
Why the other answers are weaker
- Ease into the other lane slowly so the other car can get out of the way."Ease into the other lane slowly so the other car can get out of the way." does not best answer this space management and mirror checks question. When you see a similar option on the CDL permit test, compare it against the exact safety rule and choose the answer that prevents the most immediate risk.
- Assume the car left the roadway and change lanes as normal."Assume the car left the roadway and change lanes as normal." does not best answer this space management and mirror checks question. When you see a similar option on the CDL permit test, compare it against the exact safety rule and choose the answer that prevents the most immediate risk.
Test-Day Checklist
- Read the question once for the topic, then read it again for the exact CDL action being tested in General Knowledge.
- Eliminate answers that sound convenient but skip an inspection, warning sign, or safety step.
- Say the correct rule out loud before moving on so you can recognize it when the exam changes the wording.
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Keep Studying General Knowledge
Question pages help you review one rule at a time. To build test-day speed, move back into the full General Knowledge practice test and answer a mixed set without looking at the explanation first.
State CDL Practice Paths
After you understand this answer, use a state practice path to connect the federal CDL rule with the DMV test pages drivers search for most.