The Exit action in a state is an activity or a sequence of activities that are executed when the state is exited, before the transition to the next state occurs1. The purpose of the Exit action is to perform any final actions of the current state, such as closing applications, releasing resources, logging information, etc. The Exit action is executed even if the state transitions back to the same state2.
Option A is incorrect, because the Exit action does not stop the state machine's execution, but rather prepares the state for the next transition. Option C is incorrect, because the Exit action does not revoke any entry actions, but rather complements them with any necessary exit actions. Option D is incorrect, because the Exit action does not define the conditions for the state transition, but rather executes after the conditions are evaluated.
References: 1: State 2: State Machines - Exit workflow and Trigger