What is cancer?

• A. A temporary infection caused by bacteria
• B. A disease in which damaged cells grow out of control and destroy healthy tissue
• C. A genetic disorder that affects blood clotting
• D. An autoimmune condition that attacks joints

Answer: (B)

Cancer is a disease caused by cells that have lost normal control over their growth. Normally, cells follow a regulated cycle of division and have built-in safeguards to stop when something goes wrong. In cancer, these safeguards fail, so damaged cells keep dividing unchecked and can invade nearby tissues or spread to other parts of the body. This unchecked, destructive growth is what defines cancer, not an infection, a blood-clotting disorder, or an autoimmune joint disease. The other descriptions fit those different conditions, while cancer centers on abnormal cell behavior and tissue destruction driven by genetic changes.