Answer the following question: Fact 1: Cells that divide uncontrollably may form a tumor, or abnormal mass of cells. Fact 2: For example, a fibroid is a tumor, a wart is a tumor, and cancers are tumors. Given the two facts above, when cells start to divide uncontrollablly, they may form a what?

OPTIONS: 1. anemia. 2. tissue. 3. fever. 4. cell. 5. organ. 6. fibroid. 7. acid rain. 8. illness.
Answer:
6.