Sentence Correction

Rejecting the apprenticeship model of training social workers in philanthropic agencies, twentieth-century reformer Edith Abbott was convinced of social work education belonging in the university so that students could be offered a broad range of courses dealing with social issues.

A. of social work education belonging in the university so that
B. that social work education should be in the university, and that
C. about the importance of social work education belonging in the university while
D. that social work education belonged in the university, where
E. of the necessity of social work education being in the university and
OA is d
why is option A chosen as the correct option here? i think B fit in better than A. what do you think about this or do you have a different answer with explanation? Thanks for your contribution