Hi anksm22,

In this SC, we comparing things that happened during two time frames in the past (1990 - 2000 and the 10,000 years before 1950 - 1950). For past time frames, we need to use past tense verbs. Eliminate C and D (the verb "exceeds" is present tense).

Next, we since we're dealing with a comparison, we must also follow Parallelism rules.

Answer A: "the global economy grew....more than....it did" This IS parallel ("it" parallels "the global economy" and "did" parallels "grew")
Answer B: "the growth of the global economy....was more than.....that during 10,000 years..." This is NOT parallel ("10,000 years" does NOT parallel anything).
Answer E: "the growth of the global economy....exceeded....what it did...." This is NOT parallel (the word "what" isn't parallel to anything).
Eliminate B and E.

Final Answer: A

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