408. On which fires can you use water?
Detailed Explanation
The correct answer is "b. Tires.". This question tests vehicle-fire prevention, safe response, and avoiding actions that feed a fire with more oxygen. For a differently worded version of this question, identify the hazard first and then choose the answer that preserves control, visibility, or legal compliance.
Correct Answer: b. Tires.
Why This Matters on the CDL Test
Use this as part of your General Knowledge review. The real CDL knowledge test rewards drivers who understand the reason behind each rule, not only the answer letter, so read the explanation and then try a few related questions.
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 "b. Tires." because this answer matches the safe CDL action for general knowledge knowledge. 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
- a. Electrical fires."a. Electrical fires." does not best answer this general knowledge knowledge 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.
- c. Fuel fires."c. Fuel fires." does not best answer this general knowledge knowledge 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.
Ready to practice for real?
Take our free, full-length General Knowledge practice test. Simulates the actual DMV exam with timed questions.
Start Practice TestRelated Questions
194. Name two causes of fires:
237. Which of these statements is true about causes of vehicle fires?
238. Which of these statements is true about vehicle fires?
250. You should avoid driving through deep puddles or flowing water but if you cannot, which of these steps can help keep your brakes working?
348. Which of these statements about vehicle fires is true?
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.