**Core Concept**
Cystic fibrosis is a genetic disorder that affects the **respiratory, digestive, and reproductive systems** by altering the production of **mucous and sweat**. It is caused by mutations in the **cystic fibrosis transmembrane conductance regulator (CFTR) gene**, leading to abnormal **chloride transport**. This results in thick, sticky mucus that clogs the airways and digestive tract.

**Why the Correct Answer is Right**
Although the specific correct answer choice is not provided, a common fact about cystic fibrosis is that it involves abnormal **ion transport** across epithelial cells, leading to dehydrated **airway surface liquid** and thickened mucus. The **CFTR protein** functions as a **chloride channel**, and its dysfunction leads to the disease's characteristic respiratory and digestive symptoms.

**Why Each Wrong Option is Incorrect**
**Option A:** This choice is not provided, but any option suggesting cystic fibrosis is not a genetic disorder would be incorrect.
**Option B:** Similarly, this choice is missing, but if it implied that cystic fibrosis only affects one system, it would be wrong.
**Option C:** Without the specific text, we can't address this directly, but if it suggested normal mucous production, it would be incorrect.
**Option D:** Again, without the text, we can only speculate, but if it downplayed the role of CFTR in the disease, it would be misleading.

**Clinical Pearl / High-Yield Fact**
Cystic fibrosis patients often present with **respiratory infections** and **malabsorption**, highlighting the importance of **multidisciplinary care**. Remember, cystic fibrosis is a **life-shortening** condition with significant **quality of life** implications.

**Correct Answer:**