A

Step 1: Analyze the scenario where the car is traveling towards a wall at a distance 'a' with velocity 'v'.
Step 2: If the driver decides to brake, the primary force acting on the car is the friction between the tires and the road. The stopping distance 'd' due to braking can be determined using the formula:
$$ d = \frac{v^2}{2a_{brake}} $$
where 'a_{brake}' is the deceleration caused by braking.
Step 3: If 'd' (the distance required to stop) is less than or equal to 'a', then braking is a viable option.
Step 4: If the driver chooses to turn sharply instead, this would require the car to maintain a minimum turning radius which is dependent on the speed and the coefficient of friction. The ability to turn safely depends also on the angle of the turn, the turning radius, and the speed.
Step 5: However, at high speeds, steering sharply can lead to loss of control (skidding) and is typically less safe than braking.
Conclusion: Given the options, braking is a more controlled and safer maneuver compared to turning sharply, which can result in a collision with the wall or loss of vehicle control. Therefore, the better option is to brake.