Official ExplanationThe use of antibiotics, or the life-saving mold, which was discovered by a Scottish scientist, has moved past laboratories to almost every pharmacy in the world and
have become easily available even with some skepticism when it was prescribed in 1942.A) have become easily available even with some skepticism when it was prescribed in 1942
B) has become easily available even with some skepticism when they were first prescribed in 1942
C) have become easily available even with some skepticism when first prescribed in 1942D) has become easily available even with some skepticism when the antibiotic was first prescribed in 1942E) antibiotics have become easily available even with some skepticism when it was first introduced in 1942There are two issues with this question. The first is the verb tense: have become/has become. The second is the antecedent and pronoun agreement: it/they/the antibiotic. If we can focus on one at a time, we should be able to eliminate our options and get to the correct one rather quickly:
Number One: have become / has becomeThis is an issue with parallelism & verb tenses. We can look to the original sentence for clues as to which verb tense we need:
The use of antibiotics, or the life-saving mold, which was discovered by a Scottish scientist, has moved past laboratories to almost every pharmacy in the world and have become easily available even with some skepticism when it was prescribed in 1942.The verb needs to be consistent with other verbs in the sentence AND match up with its subject, which in this case is the singular “use.” Let’s eliminate any that use the plural “have become” and keep all that use the singular “has become:”
A)
have become easily available even with some skepticism when it was prescribed in 1942
B)
has become easily available even with some skepticism when they were first prescribed in 1942
C)
have become easily available even with some skepticism when first prescribed in 1942
D)
has become easily available even with some skepticism when the antibiotic was first prescribed in 1942
E) antibiotics
have become easily available even with some skepticism when it was first introduced in 1942
We can eliminate options A, C, & E because they don’t use the same verb tense throughout, and the verb doesn’t agree with the subject. Now that we have it narrowed down to only 2 options, let’s move on.
Number Two: it/they/the antibioticThis is an issue of clarity and pronouns. We need to make sure that if we use pronouns that they agree with their antecedent and are 100% clear. If no pronouns are present, make sure the meaning is still clear:
B) has become easily available even with some skepticism when they were first prescribed in 1942This is
INCORRECT. Although the verb tense is correct since “has moved” was used earlier in the sentence, it is not clear who “they” is referring to.
D) has become easily available even with some skepticism when the antibiotic was first prescribed in 1942This is
CORRECT. The verb tense is correct and it is completely clear that antibiotics were first prescribed in 1942. When it is unclear what the pronoun is referring to, repeating the antecedent clarifies the sentence.
There you have it - option D is the correct choice! By starting with a simple “either/or” split, we can typically eliminate 2-3 options quickly and get on to more complicated issues!
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