D: An unpredictable possible set of outcomes which cannot be reliably predicted.

Everyone takes risk - buying a car, choosing a partner, or even crossing the street. Some risks are necessary, such as crossing the road. Some are not, such as parachuting. Some risks are worthwhile, such as trying new things to eat. Others are (for most of us) not worthwhile, such as recreational Russian Roulette.

Morally, any adult who chooses risk is responsible for their choice.

See