You should use the lower gears

• A. Only on flat roads
• B. When driving up and down steep hills
• C. In foggy conditions
• D. When accelerating quickly

Answer: (B)

Using lower gears gives more torque and lets the engine provide braking, which is essential on hills. When you’re climbing steep hills, a lower gear keeps the engine in its power range so you can maintain a steady, controlled pace without straining the engine. When descending, a lower gear allows engine braking to help slow the vehicle without overuse of the brakes, reducing heat and wear. That combination—more power for climbs and controlled deceleration for descents—is why the best choice is to use lower gears when driving up and down steep hills.

On flat roads you don’t need the extra torque and braking effect; in foggy conditions you should focus on visibility and smooth, safe speed; and while you can downshift for quick acceleration, that’s not the scenario described here.