answer:Having not studied Logic formally, I have no understanding at all of the symbols or application of them that you show in a. and b. That’s a total mystery to me, and I’m not going to attempt to figure it out for this response. But in your A. B. C. syllogisms: B can be a subset of A. Perhaps all of the boys like Mary best. A and C are mutually exclusive, obviously. B and C are not necessarily exclusive, since B says nothing about what “else” boys might have done. Aside from kissing the girl they liked best, they may have kissed all of the other girls, too, and even had a go at each other. The statement is silent on any ‘else’ behavior. So every boy can kiss the girl he likes best (either Mary or Sue), and then also kissed the other girl. So B can also be a subset of C.