The number of undergraduate degrees in engineering awarede 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 douibled
我选D,很本能的从The number of 判断后面是个单数,也没怎么看就选了D,答案是C,给的解释是D,E时态不对,不是很明白D的时态哪里不对?还是说D是表示了被动的含义所以才错了??