Insulin is a drug discovered in the 20th century to treat which condition?

• A. Diabetes
• B. Hypertension
• C. Arthritis
• D. Pneumonia

Answer: (A)

Insulin is a hormone used to treat diabetes, especially when the body cannot produce enough insulin or cannot use it effectively. Diabetes involves high blood glucose because pancreatic beta cells aren’t supplying enough insulin or the body's tissues are resistant to it. Replacing or supplementing insulin with injections lets glucose enter cells for energy, lowers blood glucose levels, and helps prevent dangerous complications like ketoacidosis and severe hyperglycemia. This is why insulin was discovered in the 20th century as a life-saving treatment for diabetes. The other conditions—hypertension, arthritis, and pneumonia—are caused by different processes and are managed with therapies unrelated to insulin.