To upset the apple cart means to mess up or ruin something, and in this context the person is saying that the reason why the person is a target is because they messed up.
Context: I'm just saying that maybe you're a target because you messed up or ruined something.
Hypothesis: I'm just saying that maybe you're a target because you upset the apple cart.

Given this context, is the hypothesis true (Yes/No/I don't know)?