请教gwd-1的一道语法题

Possible long-term consequences of the “greenhouse effect,” the gradual warming of the Earth’s climate, may include melting the polar ice caps and a rising sea level.

A.      may include melting the polar ice caps and a rising sea level

B.      may include the melting of polar ice caps and the rising sea level

C.      may include polar ice caps that are melting and sea levels that are rising

D.      include melting the polar ice caps and sea levels that are rising

E.       include melting of the polar ice caps and a rise in sea level

我选了B

想问一下为什么？

"may" repeats "possible" and thus is redundant.Moreover, it is not sea level of any kind but the rise that is the result.