Which sentence correctly uses a modal verb and a contrastive conjunction?

A. He might go to the party if he finishes his work on time, but he could also decide to stay home.

B. They should go for a walk in the park because it’s sunny, or they can go shopping instead.

C. She must finish her presentation by tomorrow, or she might face consequences at work.

D. We could go to the beach, yet we could also visit the mountains for a change.