With the right causation or correlation, the correct person is identified.
Whether right reason refers to being mad at the person for the related reason or the reason itself being valid and rightful, both are possible.
Right time is related to the cause of anger as well as when the anger takes place. Both is possible to be at the right time.
You can even be angry without any visible indication. There's also cases where an aggressive response is the right response. Proper response is possible too.