619. Scientific interest in providing suitable habitats for bottom-dwelling animals such as river clams arises not because they are important sources of human food
but from their role as an integral link in the Aquatic food chain.
(A) not because they are important sources of human food
(B) although they are not an important sources of human food
(C) not in that they are important as human sources of food
(D) not from their importance as a source of human food
(E) not from being important sources of food for human beings
A: Problem with parallelism. If A worked, the second half of the sentence would need to read "but because they are important sources..."
B: The article an demands a singular noun. Sources is plural. Moreover, the transition between food and but does not make sense.
C: The phrase in that is problematic here. To say "interest arises in that" is not a logical construction.
D: Sentence is parallel and the construction not from x but from y is idiomatically correct.
E: Always be wary when the word "being" appears in a sentence choice. In this choice, it is illogical to compare something being (verb) with something's role (noun).
Answer C is correct.
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