One Reason for the Actor-Observer Effect Is That

One reason for the actor-observer effect is that

A) we are more aware of how our own behavior varies than how other people's behavior varies.
B) we consider our own behavior to be unpredictable, but we find it easy to predict what other people will do.
C) when other people do the same thing we are doing, we assume they are copying us.
D) when we watch someone else behave, we usually notice the external factors that are controlling the behavior.