"In the four term contingency, the first four components of the contingency, MO, SD, and response effort determine whether or not the behavior will occur , where as the final component, the consequence determines whether or not the behavior will occur ."

Antecedent determines whether or not behavior will occur; Consequence (the final component) is  an event that occurs after the behavior, it does not determine whether or not behavior will occur however is the results of behavior.

Explanation:

A four-term contingency is something that is very important when understanding behavior; It shows how one event follows the other according to the below sequence:

Motivation>Antecedent>Behavior>Consequence

Positive reinforcement occurs when a behavior is  followed immediately by the presentation of a stimulus  that increases the future frequency of the behavior.