How is self-control best conceptualized?

A) as a reservoir
B) as a muscle
C) as a concrete foundation
D) as an infinite resource

Self-control is best conceptualized as a muscle because it can be strengthened through practice and becomes fatigued when overused. Just as a muscle needs rest to recover after a workout, self-control also needs breaks to maintain its strength. Theories of ego depletion suggest that self-control is a limited resource that can be depleted over time, which supports the idea of it being a muscle that can become fatigued.