GMAT Sentence Correction (SC) | Almost the whole of Yellowstone National Park is located in one of the

Almost the whole of Yellowstone National Park is located in one of the world’s largest volcanic craters; the question isif the recent increased activity of the park’s geysers and hot springs indicate that the volcano has become active.

(A) if the recent increased activity of the park’s geysers and hot springs indicate that the volcano has become active.
(B) if recently observed increases in the activity of the park’s geysers and hot springs indicate that the volcano has become active.
(C)
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