Which of the following is an autoimmune disease of the digestive system?

• A. Lactose intolerance
• B. Gastroenteritis
• C. Celiac disease
• D. Peptic ulcer

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the term 'autoimmune disease.' Autoimmune diseases occur when the immune system mistakenly attacks the body's own tissues, thinking they are foreign invaders.
2. Step 2: Review the options provided and identify which conditions involve the immune system attacking the body's tissues. Lactose intolerance is a digestive issue caused by the inability to digest lactose, not an autoimmune condition. Gastroenteritis is an infection or inflammation of the digestive tract, typically caused by pathogens, not the immune system.
3. Step 3: Examine 'Celiac disease.' Celiac disease is an autoimmune disorder where the immune system attacks the lining of the small intestine in response to gluten consumption, leading to damage and malabsorption of nutrients.
4. Step 4: Consider 'Peptic ulcer.' Peptic ulcers are sores in the stomach lining or upper small intestine, often caused by Helicobacter pylori bacteria or excessive use of NSAIDs, not an autoimmune response.
5. Step 5: Conclude that the correct answer is 'Celiac disease,' as it is the only condition listed that fits the definition of an autoimmune disease affecting the digestive system.