Multiple Choice Slide Design

I notice that when I enter details into Form view for a Multiple Choice question, the answer slots are labeled "A", "B", "C", etc. Is it possible to have these letters automatically added to the slide, or would they have to be added manually in Slide view?

If I have to add them manually, can you offer any advice on getting things to line up? I've added the letters as text boxes, and then used the Arrange tools to line things up, however when I preview the slide, things move out of alignment.

The reason I'm needing to do this is that some of the answers in the quiz refer to each other.

Any help appreciated!