Final answer:
Motorists should rest after 2 hours of driving to maintain concentration and reduce the risk of accidents due to driver fatigue. Resting regularly is a key part of a safe driving plan.
Step-by-step explanation:
It is generally recommended for motorists to take a rest after 2 hours of driving to prevent fatigue. Therefore, the correct answer is 2 hours.
Resting while on a long journey is important for maintaining concentration and safety on the road. Ignoring this advice can lead to a greater risk of accidents due to driver fatigue.
The safest practice is to plan the journey with regular breaks, stretching your legs, having a snack, or simply resting from the driving activity.