## Core Concept
Celiac disease is an autoimmune disorder where the ingestion of gluten leads to damage in the small intestine. It is characterized by an immune reaction to **gluten**, a protein found in **wheat**, **barley**, and **rye**. Management involves a strict **gluten-free diet**.

## Why the Correct Answer is Right
Oats are often considered safe for individuals with celiac disease, provided they are **gluten-free**. While oats contain a protein called **avenalin**, which is similar to gluten, pure oats do not contain gluten. However, cross-contamination with gluten-containing grains during processing is a concern. Some patients with celiac disease may react to oats due to **avenalin**, but this is less common. Oats are generally considered an acceptable part of a gluten-free diet when properly sourced.

## Why Each Wrong Option is Incorrect
* **Option A:** Wheat contains **gluten** and is a primary grain to be avoided in celiac disease.
* **Option B:** Barley also contains **gluten** and should be avoided.
* **Option D:** Rye contains **gluten** and is contraindicated in patients with celiac disease.

## Clinical Pearl / High-Yield Fact
A key point to remember is that while oats are generally safe, it's crucial to choose oats that are **certified gluten-free** to avoid cross-contamination with gluten-containing grains. Patients with celiac disease should always read food labels carefully and consult with a healthcare provider or dietitian for guidance on a gluten-free diet.

## Correct Answer: .