So I normally use the word Climax but I'm assuming that climax and main action are the same thing. The main action is definitely (B) - Mary's husband tells her that he is leaving her, because that is what starts the suspense.
Please tell me if that isn't right, I think it is.
Rain: connotation is that of abundance, overabundance, or just sheer magnitude. ... The second connotation is sadness, melancholy, distress, or even foreboding. Use of rain or impending rain in movies to convey such these things is almost a trope.