Final answer:
Blood in the stool can be a sign of colorectal cancer. A colonoscopy can help diagnose and treat the condition.
Step-by-step explanation:
When someone has blood in their stool, it can be a sign of various conditions, including colorectal cancer. A colonoscopy is a diagnostic and therapeutic procedure that can help identify and remove precancerous polyps before they become malignant. It is recommended for those over 50 years of age as part of cancer screening.