What should drivers be aware of if they meet horses with riders on the road?

Drivers should be aware that horse riders are obliged to dismount and control their horses while traffic is passing.
Drivers should be aware that all horse riders are experienced at handling horses.
Drivers should be aware that loud noises from their vehicle may frighten the horses and cause them to bolt.
Drivers should be aware that loud noises from their vehicle will not frighten the horses.

Explantion: You must know your responsibilities towards animal traffic on the road. Horses are easily startled and any sudden noises or activity could cause them to bolt.

Theory Tester

What should drivers be aware of if they meet horses with riders on the road?

Safe and Responsible Driving