下列动物中生殖发育离不开水域环境的是（　　）

A．家鸽

B．蟾蜍

C．家兔

D．壁虎

Seawater may be used for drinking（）.

A.under no conditions

B.at a maximum rate of two ounces per day

C.if gathered during or immediately after a hard rain

D.after mixing with an equal quantity of fresh water