The answer is: [A]: fragment .
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The phrase: "Since each group depends upon the other groups."
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is NOT correct as it is — thus eliminating "Answer choice: [C]: correct" ;
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and is NOT a 'run-on sentence' — thus eliminating
"Answer choice: [B]: run-on" .
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Rather, the phrase:
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"Since each group depends upon the other groups." ;
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is a sentence FRAGMENT; which is the remaining answer choice given—
"Answer choice: [A]: fragment" .
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