The body's largest organ is _________.

• A. The skin
• B. The liver
• C. The heart
• D. The brain

Answer: (A)

The skin is the body's largest organ because it forms the outer covering that blankets the entire body, giving it a huge surface area and substantial mass. In an average adult, it spans roughly 2 square meters (about 20–22 square feet) and weighs several kilograms, which makes it larger than internal organs such as the liver, heart, or brain. The skin is part of the integumentary system and consists of the epidermis and dermis (with subcutaneous tissue beneath). It serves as a protective barrier against microbes and injury, helps regulate temperature through sweating and blood flow, and houses sensory receptors for touch, temperature, and pain. All of these features together explain why the skin is considered the body's largest organ.