AbdurRakib
Although
malaria was once universally believed to have been introduced to Native American populations by 16th-century European explorers, the recent excavation of a 10th-century mass grave of Native American malaria victims has caused many historians to reconsider their chronologies of European incursion into the Americas.
(A) malaria was once universally believed to have been
(B) malaria was at one time universally believed as being
(C) malaria, once universally believed to be
(D) malaria was at one time universally believed as having been
(E) malaria, once universally believed as being
Official Explanation:
This sentence is correct as written.
The underlined portion of the sentence contains the present perfect tense have been so make sure this is the proper verb tense. The underlined portion of the sentence also contains the idiom believed to, so check for idiom errors. The sentence describes a former belief (recent excavation...has caused many historians to reconsider), so the past tense believed is correct. This former belief concerned when malaria was first introduced, so the present perfect have been is correct. The idiom believed to is the correct idiom. There appears to be no error in the original sentence, so keep choice A. Because there is no error in the original sentence, there are no obvious repeaters to look for, so evaluate the remaining answer choices individually looking for reasons to eliminate each.
Choice B incorrectly states believed as being. The sentence calls for the present perfect tense, and the idiom structure believed…as is incorrect. Eliminate choice B. Choice C uses believed to be. While believed to is idiomatic, in this case the use of the present tense verb be is not correct. The former belief in this sentence concerns an occurrence in the past, therefore the sentence calls for the present perfect tense. Eliminate choice C. Choice D incorrectly states believed as having been. The sentence calls for the present perfect tense, and the idiom structure believed…as is incorrect. Eliminate choice D. Choice E incorrectly states believed as being The sentence calls for the present perfect tense, and the idiom structure believed…as is incorrect. Eliminate choice E.
Choice A: Correct.
Choice B: No. Believed…being is the wrong verb tense and believed…as is an incorrect idiom. Verb tense; Idiom.
Choice C: No. The present tense verb be is the incorrect tense for this sentence. Verb tense.
Choice D: No. Believed…having been is the wrong verb tense and believed…as is an incorrect idiom. Verb tense; Idiom.
Choice E: No. Believed…being is the wrong verb tense and believed…as is an incorrect idiom. Verb tense; Idiom.
The correct answer is choice A.