Which of the following will increase the effects of alcohol and drugs when boating?

The choice that indicates a factor increasing the effects of alcohol and drugs while boating is vibration. When a vessel is in motion, particularly in rough waters, the vibrations can have a physiological effect on the body. This response is compounded if an individual has consumed alcohol or taken drugs, as both can impair cognitive functions and physical coordination.

Vibration can cause distractions and a heightened sense of disorientation, which, when paired with the impairing effects of substances, can lead to poor decision-making and slower response times while operating a boat. This makes it crucial for boaters to remain aware of how such conditions can amplify the risks associated with alcohol and drug consumption.

Other factors like excessive sunlight, fast currents, and low temperature do contribute to a boater's overall experience and affect fatigue, thermal regulation, or adrenaline levels. However, vibration specifically relates to how the body reacts to impairments caused by substances, creating a direct correlation with increased intoxication effects while navigating on water.