What factor should be considered to avoid overheating brakes when descending a hill?

To avoid overheating brakes when descending a hill, shifting to a lower gear is the most effective strategy. By using a lower gear, you enable engine braking, which helps to control your vehicle's speed without relying solely on the brake system. This reduces the demand on the brakes, decreasing the risk of overheating.

When a vehicle descends a hill, the gravitational pull can cause it to gain speed rapidly. If you rely only on the brakes to slow down, it can lead to excessive heat buildup in the brake components. Shifting to a lower gear allows the engine to assist in slowing the vehicle, effectively reducing the amount of braking needed and helping to maintain a safer, more controlled descent.

Each of the other options would not effectively manage the risk of brake overheating. For example, maintaining high speed increases the need for braking, which can lead to overheating. Activating emergency brakes is typically reserved for severe situations and may not be effective or safe during typical descents. Using both brakes and the accelerator may lead to increased wear on the braking system while not effectively reducing the vehicle’s speed.