What is a common risk when riding without a helmet?

Riding without a helmet significantly increases the risk of severe head injuries in the event of an accident. Helmets are specifically designed to absorb impact and protect the brain from trauma, which can lead to life-altering consequences or even fatalities. Without this protective gear, riders expose themselves to a greater likelihood of sustaining serious injuries, such as concussions, skull fractures, or other traumatic brain injuries.

The other choices, while they may imply benefits, are not relevant to the safety concerns associated with helmet use. Increased visibility, road grip, and reduced wind resistance do not outweigh the critical protection that a helmet offers in safeguarding a rider's head during a crash. The focus on safety and injury prevention underlines the importance of wearing a helmet while riding.