GWD 9-27 没搜到，请指点！

Scientists have identified an asteroid, 2000 BF19, that is about half a mile wide and, if it strikes Earth, it can do tremendous damage to part of the planet but probably not cause planetwide destruction.

A.      and, if it strikes Earth, it can do tremendous damage to part of the planet but

B.      and, if it would strike Earth, part of the planet could experience a tremendous amount of damage but it would

C.     and that, if it were to strike Earth, could do tremendous damage to part of the planet but would

D.     and that, if Earth is struck by it, can do part of the planet tremendous damage, but it would

E.      and that, if it strikes Earth, it could experience a tremendous amount of damage but

答案是C。但是新东方老师说过BE TO结构是GMAT里面的错误用法吗？所以，一看到WERE TO，我就把C排除了。我选了A。请大家指点，为什么A不对啊？

there you go:

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