Answer:
D. Theme
Step-by-step explanation:
The theme is the general underlying message that the writer is trying to pass. The mood, though, creates an emotional setting. A theme and a mood are not dependent on each other but they can help each other to build a scene.
If your theme is "overcoming adversities", using a mood that evokes frustration for a long time until it changes drastically to happiness of fulfillment after the adversity is overcame can be a great way to use mood to help with your theme.