Why does the Falun Gong pose a potential threat to party leaders in China?

a. It proclaims itself to be a religious cult with a strong political agenda.
b. It claims a following in China of over 70 million people, roughly the same amount as the CCP.
c. It uses underground magazines to distribute pro-democracy propaganda.
d. It is the central religion of Tibetans who have worldwide support in their efforts to gain independence.

b