Final answer:
C.) They reduce the capacity to perform good shoulder checks and can cause the motorcyclist to tire easily.
Road race or clamp-on handlebars increase the capacity to execute good shoulder checks and ensure the motorcyclist doesn't get tired quickly.
Step-by-step explanation:
The role played by road race or clamp-on handlebars in motorcycles is to increase the capacity to execute good shoulder checks and ensure the motorcyclist doesn't get tired quickly. By providing a more aerodynamic riding position, these handlebars allow the motorcyclist to maintain better control and stability at high speeds. This improved control also enhances the motorcyclist's ability to perform shoulder checks effectively, reducing the risk of accidents.