What is a possible and typical meaning for someone who dreams about falling off a ladder?

c. the person is feeling insecure in real life. the person is uncomfortable with heights.

a. the person is feeling elation, and the fall is really freedom.

b. the person is confident and testing his boundaries?

People get on stuff only when they feel secure (someone is holding the ladder down there), they know the consequences and are fearless about facing them (I'll fall and it'll hurt but hey, I'll live), or they have the experience. Think about it, who willingly jumps off a ladder? Maybe if they were tied to a cord or something, they wouldn't do that. Also, look at it technically, you clearly mentioned said person falls off the ladder. So, the options you gave is too limited to put into theory. I've given you enough insight to see it. Knowing this, what does falling off a ladder mean?

Failure.