Going through why each of the incorrect answers are wrong is making things more confusing. The way I generally interpreted why the incorrect answers are wrong is that they weaken the argument by introducing plausible alternative hypothesis. I don't know if this is the ideal way to rule these out. It feels like the incorrect answers can be interpreted in sooo many different ways and that my interpretation is never the same as the explanations'.

Is saying A can not occur and B can occur (/A and B) still a negation of the conditional instead of saying A can occur and B not occur (A and /B)?