I put down (B) rather than (C) for the ... effect (i.e. Whether b-g 's in general do ... Thus, to say that b-g branching triggers immuno-effects ... in the passage, whereas (B), which only mentions that if ... that shroom must be making b-g 's.
I am assuming that everyone here wants to become an attorney, so I just wanted to pose a question, which has been on my mind for the last couple of days.