**Core Concept**
The question is testing the knowledge of strategies to reduce the hereditary risk of ovarian cancer in women with BRCA-1 and BRCA-2 mutations. This involves understanding the role of genetic mutations in cancer development and the preventive measures available to mitigate this risk.

**Why the Correct Answer is Right**
Women with BRCA-1 and BRCA-2 mutations have a significantly increased risk of developing ovarian cancer. **Prophylactic salpingo-oophorectomy**, which is the surgical removal of the ovaries and fallopian tubes, is a recommended strategy to reduce this risk. This procedure is often recommended for women with BRCA mutations who are over 35 years old and have completed childbearing. The removal of the ovaries and fallopian tubes eliminates the risk of ovarian cancer, which is a major concern for these women.

**Why Each Wrong Option is Incorrect**
**Option A:** Chemoprevention with tamoxifen is not recommended for ovarian cancer prevention in BRCA-1 and BRCA-2 mutation carriers.
**Option B:** Screening with CA-125 and transvaginal ultrasound is not effective in reducing ovarian cancer mortality in high-risk women.
**Option C:** Breast cancer screening with mammography and MRI is not a strategy to reduce ovarian cancer risk.

**Clinical Pearl / High-Yield Fact**
Women with BRCA-1 and BRCA-2 mutations should be counseled about the risks and benefits of prophylactic salpingo-oophorectomy, and this should be considered as part of a comprehensive risk-reduction plan.

**Correct Answer:** C. Prophylactic salpingo-oophorectomy.