______ percent of all cancers could be averted if people ate more fruits, vegetables, and plant-based foods and minimized high-fat, high-calorie edibles.

A．When they wanted to kill an enemy.
B．When they wanted to identify a stranger.
C．When they wanted to tell the time of the day.
D．When they wanted to send a message to a person far away.

A．A small horse
B．Cigarettes
C．A mirror
D．Fire arrows