You can only get one test out of any type of conflict. I think you’re supposed to take the first test of the conflict, unless you’re one test away from advancement and you need a specific difficulty. (Actually, that last part may be me conflating Mouse Guard in there, but I can’t remember.)
B is correct. You get one test for each ability used in the conflict. Usually the highest difficulty, unless you’re one test away from advancing, in which case you can take the lower difficulty test if it comes up.