What is one limitation of a Class M learner's permit for motorcycle operation?

A Class M learner's permit requires the operator to wear a helmet while riding a motorcycle. This rule is in place to enhance safety and reduce the risk of serious injury in the event of an accident. The helmet serves as a critical piece of protective gear for novice motorcyclists who may still be developing their riding skills and are thus more vulnerable to hazards on the road. Wearing a helmet is not just a regulation; it is a vital safety precaution that can significantly improve the chances of survival and reduce the severity of head injuries.

The other choices pertain to different aspects of motorcycle operation under a learner's permit but do not highlight specific limitations dictated by regulations. For instance, there are restrictions related to carrying passengers and riding at night, but these can vary by jurisdiction. The choice regarding riding only on highways is incorrect because it doesn't accurately represent the typical limitations of learners under a Class M permit. Hence, wearing a helmet is the most definitive and enforceable limitation consistently emphasized in safety regulations.