Hi, I am having a little trouble in such short sentences. If possible, along with the answers plz give the rule that I can apply. Tq!

1. In the 1980s, the rate of increase of the minority population of the United States was nearly twice as fast as the 1970s.

A. twice as fast as
B. twice as fast as it was in
C. twice what it was in
D. two times faster than that of
E. two times greater than

2. Employment costs rose 2.8 percent in the 12 months that ended in September, slightly less than they did in the year that ended in the previous quarter.
A. less than they did
B. less than it did
C. less than they were
D. lower than
E. lower than they were