Writing>Improving Sentences

Part or all of the following sentence is underlined;beneath the sentence are five ways of phrasing the underlined material.Select the option that produces the best sentence.If you think the original phrasing produces a better sentence than any of the alternatives,select choice A.

It is thought that a dog's sense of smell is generally 10,000 to 100,000 times better than humans.

(A) humans
(B) humans'are
(C) humans have
(D) a human's
(E) a human has

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