Sentence Correction

While arts management programs and other similar courses are often seen as a requirement to be eligible for jobs such as museum curating, in fact they ought to be considered optional: a degree in management studies is by no means a necessary qualification for the understanding of art.
A. While arts management programs and other similar courses are often seen as a requirement to be eligible for jobs such as museum curating, in fact they ought to be considered optional: a degree in management studies is by no means a necessary qualification for the understanding of art.
B. Though arts management programs and other similar courses like them are often seen as a requirement to be eligible for jobs such as museum curating, they should in fact be considered optional, a degree in management studies is by no means a qualifying necessary qualification for the understanding of art.
C. A degree in management studies is by no means a necessary qualification for the understanding of art, thus arts management programs and other similar courses are often seen as a requirement to be eligible for jobs such as museum curating, but in fact they ought to be considered optional.
D. Though a degree in management studies is by no means a necessary qualification for the understanding of art, it should, in fact, be considered optional: arts management programs and other similar courses are often seen as a requirement to be eligible for jobs such as museum curating.
E. Arts management programs and other similar courses are often seen as a requirement to be eligible for jobs such as museum curating, but a degree in management studies is by no means a necessary qualification for the understanding of art: in fact, they ought to be considered optional.
OA is a

what is wrong with option A and B in this question? can any expert help me with the correct answer?
Thanks