Let's rule out C and D based on "meeting." One meets someone once. You may discuss the meeting (noun) later, but in fact, they met. Once. It cannot be a continuous (-ing) action. And now they know each other and are married and living happily ever after. You may change meeting to beating and the sentence makes sense, but - happily - that's not the intent.
So now, debate options A and B. I see no difference in either.