The compound sentence is:
D. After the boy ate a tofu hot dog, he wiped his face, and then he went out to play.
Explanation:
1. A compound sentence consists of two or more independent clauses joined by coordinating conjunctions like "and," "but," or "or."
2. In sentence D, there are two independent clauses:
- "After the boy ate a tofu hot dog, he wiped his face."
- "Then he went out to play."
3. The independent clauses in sentence D are joined by the coordinating conjunction "and," making it a compound sentence.