Undersea life decreases with ______ depth; in very deep waters, light levels, salinity, and amount of oxygen tend to limit the number of species available.

A、 impending
B、 diminishing
C、 subterranean
D、 minimal
E、 increasing

【正确答案】 E

【答案解析】Work backward to fill in the blank. The number of species is limited in very deep waters; therefore, undersea life decreases with increasing depth, and the answer is choice E.