a question

monica

Since 1986 enrollments of African Americans, American Indians,and Hispanic Americans in full-time engineering programs in the United States (has steadily increased,while the number of other students who enter the field has fallen.)

(c) increased steadily,while there was a decline in the number of other strdents entering the field.
(d) have steadily increased,while the number of other students entering the field has fallen.

which one is correct?

peter

Of the three selections,d is  the best.

zyh79

补充：
a。enrollments：入学人数，复数形式，has steadily increased错
c.有since短语，increased steadily错
其实，这里enrollments和the number 视可以并列的，都表示人数
enrollment作参加讲，不可数

monica

thanks.