What Is the Relationship Between the Terms "Mood" and "Emotion

What is the relationship between the terms "mood" and "emotion?"

A) A mood is part of an emotion, but an emotion is not part of a mood.
B) An emotion is a response to a specific stimulus, while a mood is a more general free-floating feeling that does not relate directly to a stimulus.
C) An emotion is part of a mood, but a mood is not a part of an emotion.
D) A mood has an affective component, while an emotion has an expressive and a physiological component.