Which principle holds that an individual assumes certain risks when participating in a particular activity?

The principle that best describes the concept where an individual assumes certain risks when participating in a particular activity is known as assumption of risk. This legal doctrine implies that when individuals engage in activities that have inherent risks—such as sports, recreational activities, or other potentially hazardous endeavors—they are acknowledging and accepting the risks involved.

Under this principle, if a participant chooses to engage in an activity after being made aware of the risks, they may be precluded from recovering damages for injuries incurred as a result of those risks. For example, a player in a contact sport understands that there is a risk of injury from collisions and accepts that risk simply by participating.

The other principles listed relate to different legal concepts. Contributory negligence involves a situation where a plaintiff may be found partially at fault for their injuries, potentially barring recovery of damages. Res ipsa loquitur is a doctrine used to establish negligence based on the mere occurrence of an accident, implying that the cause was likely due to the defendant's lack of care. Comparative negligence allows for damages to be assigned based on the degree of fault of each party. These principles do not specifically address the proactive acceptance of risk by an individual in the same way that assumption of risk does.