Sentence Correction

Many physicists think that at some time in the next century we will not only discover life in other galaxies but will also communicate with them.

A)we will not only discover life in other galaxies but will also communicate with them.
B)we will discover not only life in other galaxies, but be able to communicate with it.
C)we will not only discover life in other galaxies but we will be able to communicate with it.
D)that not only will we be able to discover life in the other galaxies but be able to communicate to them as well.
E)not only ot find life in other galaxies but to communicate with it as well.

[spoiler]
Third choice is the correct choice. The orignal contains an error of pronoun usage: them fails to agree in number with its referent, life. The third choice solves this problem by substituting it for them. The second choice corrects the error found in the orignal, but it changes the intended meaning of the orignal. The second choice asserts that something in addition to life will be found in other galaxies. As for the fourth choice, the that seems to introduce a noun clause, but the noun clause has already been introduced by an earlier that. Thus, everything contained in the fourth choice is left with no logical connecton to the rest of the sentence. As for the fifth choice, since the that sets up a noun clause, you need a subject and a conjugated verb for the clause. The resulting of using the fifth choice would be a phrase lacking a subject and a conjugated verb.
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