请教另外一道GWD语法题

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.

1. in addition to its possibilities for preventing and inhibiting
2. in addition to its possibilities to prevent or inhibit
3. besides the possibility that it prevents and inhibits
4. besides the possible preventing and inhibiting of
5. besides possibly preventing or inhibiting

请问正确答案是E，我怎么也想不通啊 我一直在B和C中选，结果都不对！请教高手为什么选E？

先说句，不是高手哈。

in addition to是除了***（没有**）

besides 是除了**，还有**

选F．besides possibly preventing or inhibiting

因为题目意思是除了possibly preventing or inhibiting ，（还有）the brewed leaves of Camellia sinensis may 也play a role

个人想法：

1，AB的错误不在于in addition to，而在于it不对，虽然作为代词先行，和后面的主语对不上；相同现象有C

2，D不好，the possible preventing and inhibiting of。。。用一个动名词太抽象，不如E那么直接用分词表达动作