Accidents are unfortunate events that happened unintentionally, while risky behaviors usually intentional even though the negative effects are already known.
One example of accidents is if plane passengers died during the plane crash. And the example of a risky behavior is to use tobacco product despite the negative effects it has on health.
B, sanitizing.
When you use hand sanitizer or hand soap, you are using chemicals to kill off the bacteria. Washing/rinsing your hands only moves the bacteria, and doesn't kill them. Air drying your hands does not in anyway kill germs. <span />
According to the exercise principle of balance, a workout should __________.
D.
vary exercise activities over time
