In this task, you need to write a topic word from the given fact. The topic word must have at least one word overlap with the given fact. The topic word often involves adding a new word from a related concept. In your topic word, use at least one word from the given fact. Topic words with two or more words work best.

[EX Q]: Fact: Muscles can only contract.
[EX A]: contract leg.

[EX Q]: Fact: Invertebrates are animals that lack a vertebral column, or backbone.
[EX A]: Invertebrate.

[EX Q]: Fact: Sperm are deposited in the vagina during sexual intercourse.
[EX A]:
male gametes sperm.