Charles Darwin, a young man just out of university, knew perfect well that he had to depend on _____ when he set out on a voyage of discovery around the world.

A．him

B．himself

C．themselves

D．them

有关饱和溶液的下列说法正确的是（　　）

A．同种溶质的饱和溶液，一定比它的不饱和溶液的浓度大

B．在饱和溶液里，再加入任何物质都不能溶解

C．某饱和溶液当温度升高时，若溶液的质量不变，则溶液的浓稀程度也不变

D．在某种溶质的饱和溶液中再加入这种溶质，溶液的质量也增加