请教大全449

1.        It seems likely that a number of astronomical phenomena, such as the formation of planetary nebulas, may be caused by the interaction where two stars orbit each other at close range.

(A) may be caused by the interaction where two stars orbit each other

(B) may be caused by the interaction between two stars that each orbit the other

(C) are because of the interaction between two stars that orbit each other

(D) are caused by the interaction of two stars where each is orbiting the other（E）

(E) are caused by the interaction of two stars orbiting each other

正确答案E,我选的是B, E把原选项的may去调了,不是说情态动词不能随意的添加和丢失吗

不等于说不能添加或丢失。

这里去掉may be是因为未划线部分有 seems likely了和may be并用语意重复，大家都是一种不确定的语气。