Hi aashu4uiit,
Thank you for your question. Let's look the clear differences between each answer, and tackle them one at a time:
1. Parallel structure in the "not X, but Y" idiom
2. Use of comma versus semicolon
Let's start with parallel structure because it should narrow down the most answers. For the idiom to work, it needs to be structure "not as an X, but as a Y."
a) not
as an adversary but
a friend , a fact that was obvious (NOT PARALLEL)
b) not
as an adversary but
as a friend ; a fact that was obvious (PARALLEL)
c)
as not an adversary but
as a friend , a fact that was obvious (NOT PARALLEL)
d)
as a friend not
as an adversary, an obvious fact (NOT PARALLEL/WRONG STRUCTURE)
e) not
as an adversary but
as a friend , a fact that was obvious (PARALLEL)
Based on using parallel structure, we can eliminate answers A, C, & D. Now that we're left with answers B & E, let's look at #2 on the list: punctuation.
b) not as an adversary but as a friend; a fact that was obvious
This is WRONG because it uses a semicolon incorrectly. Semicolons can only be used when there are independent clauses before and after the semicolon. In this case, the clause after the semicolon can't stand alone and is dependent.
e) not as an adversary but as a friend, a fact that was obvious
This is the CORRECT answer because it uses proper parallel structure AND uses a comma, which is the correct punctuation for an independent clause + dependent clause.
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