It’s the same in China—many people, some ______ are not overweight at all, are always going

on diets or taking weight-loss pills, ______ are often dangerous.

A．whose; which

B．of which; who

C．of whom; which

D．who; that

用氢气、木炭粉、一氧化碳分别还原等质量的氧化铜，所需三种还原剂的质量比是[ ]

A．1:1:1

B．1:6:14

C．1:3:14

D．14:3:1