If your vehicle has a two-part safety belt system, you should:
- Use only the lap belt.
- Use both the lap and shoulder belts. ✓
- Use only the shoulder belt.
Answer: B. Use both the lap and shoulder belts.
Use both the lap belt and shoulder belt.
Why this is the answer
California's handbook ties survival in most collisions to wearing the lap belt and shoulder harness together. It also explains correct placement for each part: the shoulder portion crosses your chest with little slack, and the lap portion sits snug and low across your hips. A two-part system is designed to be worn as a pair, so using both parts matches the handbook's instruction. Skipping either part leaves you without the placement the handbook describes.
Why the other answers are wrong
- A. Use only the lap belt. — Using only the lap belt leaves the shoulder portion unused, even though the handbook describes wearing the lap belt and shoulder harness together and gives placement for both.
- C. Use only the shoulder belt. — Using only the shoulder belt ignores the lap portion, which the handbook says should be snug and low across your hips.
Remember it
Match the belt to your body: lap low across hips, shoulder across chest.
Official handbook: California Driver Handbook (DL 600), Section 8: Safe Driving, p. 65