GWD 7-Q33:

The health benefits of tea have been the subject of much research; in addition to its possibilities for preventing and inhibiting some forms of cancer, the brewed leaves of Camellia sinensis may also play a role in reducing the risk of heart disease and stroke.

in addition to its possibilities for preventing and inhibiting in addition to its possibilities to prevent or inhibit besides the possibility that it prevents and inhibits besides the possible preventing and inhibiting of

besides possibly preventing or inhibiting

why the answer is E? should besides be followed by an noun or something?