Sentence Correction

According to a study by the Carnegie Foundation for the Advancement of
Teaching, companies in the United States are providing job training and general
education for nearly eight million people, about equivalent to the enrollment of
the nation's four-year colleges and universities.

(A) equivalent to the enrollment of
(B) the equivalent of those enrolled in
(C) equal to those who are enrolled in
(D) as many as the enrollment of
(E) as many as are enrolled in

Ans E

I would have chosen C.

can anyone explain...

deepak123gmat wrote:According to a study by the Carnegie Foundation for the Advancement of
Teaching, companies in the United States are providing job training and general
education for nearly eight million people, about equivalent to the enrollment of
the nation's four-year colleges and universities.

(A) equivalent to the enrollment of
(B) the equivalent of those enrolled in
(C) equal to those who are enrolled in
(D) as many as the enrollment of
(E) as many as are enrolled in

Ans E

A and D: Illegal comparison of Number of people to the enrollment of colleges. Colleges are not enrolled but the people.
B,C and E all seem correct to me but E is concise and clear and unlike B and C it is not wordy.

IMO E