GMAT Sentence Correction (SC) | The law of conservation of energy states that energy

Idiom:Neither X nor Y ==> X and Y must be parallel.

The law of conservation of energy states that energycan neither be created or destroyed.

1) can neitherbe created or
Parallel problem

2) can be neither createdor
Idiom problem

3) canneither be created nor
Parallel problem

4) can be neither created nor
Correct.
5) cannot either be created or be
"Neither X nor Y" is much better than "not either X or Y"

Hope it helps.
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