Children who are not active or__________diet is high in fat will gain weight quickly.

A．what

B．whose

C．which

D．that

在洞穴里探险，不时停下来歇一会儿，可节省体力。休息时关上电筒，以免浪费电力，把电池靠近身体暖一下，也能用得久些。