**Core Concept**
The question is asking about the genetic predisposition to ovarian cancer, specifically focusing on familial cases. Familial ovarian cancer has been linked to mutations in specific genes that increase the risk of developing this disease.

**Why the Correct Answer is Right**
The genes most closely associated with familial cases of ovarian cancer are BRCA1 and BRCA2. These genes encode for tumor suppressor proteins that play a crucial role in maintaining genomic stability. Mutations in these genes lead to an increased risk of breast and ovarian cancer. The BRCA1 gene is involved in DNA repair mechanisms, particularly in the repair of double-strand breaks through homologous recombination. The BRCA2 gene is also involved in DNA repair, but its function is more closely related to the repair of interstrand crosslinks. Women with mutations in either of these genes have a significantly increased risk of developing ovarian cancer.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not specify a known gene associated with familial ovarian cancer.
* **Option B:** This option is incorrect because it is a gene associated with familial breast cancer, but not specifically with ovarian cancer.
* **Option C:** This option is incorrect because it is a gene associated with familial colon cancer, but not specifically with ovarian cancer.

**Clinical Pearl / High-Yield Fact**
It is essential for clinicians to identify individuals with a family history of breast and ovarian cancer, as they may be at increased risk of developing these cancers due to inherited genetic mutations.

**Correct Answer:** C. BRCA2.