**Core Concept**
Call-Exner bodies are a type of histopathological feature associated with granulosa cell tumors of the ovary. These structures are small, round or oval collections of cells that form within the tumor stroma, typically consisting of Call-Exner bodies and a central space.

**Why the Correct Answer is Right**
Call-Exner bodies are characteristic histological features of granulosa cell tumors, which are sex cord-stromal tumors of the ovary. They are formed by a group of granulosa cells that accumulate around a central space, often containing eosinophilic material or a fluid-filled space. This unique histological feature helps in the diagnosis and distinction of granulosa cell tumors from other ovarian neoplasms.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because Call-Exner bodies are not typically seen in epithelial ovarian tumors, such as serous or mucinous cystadenocarcinomas.
**Option B:** This option is incorrect because the presence of Call-Exner bodies is not a characteristic feature of thecomas, which are also sex cord-stromal tumors but have a different histological appearance.
**Option C:** This option is incorrect because Call-Exner bodies are not seen in stromal tumors of the uterus, such as leiomysosarcomas.
**Option D:** This option is incorrect because Call-Exner bodies are not a feature of metastatic tumors to the ovary.

**Clinical Pearl / High-Yield Fact**
Call-Exner bodies are a key diagnostic feature of granulosa cell tumors, which are typically seen in young women and can present with signs and symptoms of estrogen excess, such as menstrual irregularities and endometrial hyperplasia.

**Correct Answer:** C. Granulosa cell tumors