请问OG72题

72. The number of undergraduate degrees in engineering awarded by colleges and universities in the United
States increased by more than twice from 1978 to 1985.
(A) increased by more than twice
(B) increased more than two times
(C) more than doubled
(D) was more than doubled
(E) had more than doubled

In OG's explanation, D's passive verb was ... doubled suggests without warrant that some unnamed agent
increased the number of engineering degrees.

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