## **Core Concept**
Sjögren's syndrome is a chronic autoimmune disorder characterized by its hallmark symptoms: dry eyes (xerophthalmia) and dry mouth (xerostomia). This condition results from the immune system mistakenly attacking the glands responsible for tear and saliva production.

## **Why the Correct Answer is Right**
The correct answer refers to the exocrine glands, specifically the lacrimal and salivary glands. In Sjögren's syndrome, the immune system targets these glands, leading to inflammation and destruction of the glandular tissue. This results in reduced tear and saliva production, causing the characteristic dryness. The condition can also affect other exocrine glands and sometimes involves extraglandular manifestations.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is incorrect because Sjögren's syndrome specifically involves the exocrine glands, not the endocrine glands. Endocrine glands secrete hormones directly into the bloodstream.
- **Option B:** This option is incorrect as it refers to the nervous system, which is not directly involved in the primary pathology of Sjögren's syndrome.
- **Option C:** This option might seem plausible because Sjögren's can have systemic effects, but it is not the most accurate description of the primary disease process.

## **Clinical Pearl / High-Yield Fact**
A key clinical pearl is that patients with Sjögren's syndrome are at increased risk of developing **lymphoma**. Additionally, the condition often presents with symptoms of dry eyes and mouth, but systemic manifestations can occur. A classic association is with **rheumatoid arthritis** and **lupus**, as part of the spectrum of connective tissue diseases.

## **Correct Answer:** . Exocrine glands.