Final answer:
A 45-year-old woman who has never been pregnant is more likely to have an increased risk of ovarian cancer due to factors such as more ovulatory cycles and greater exposure to estrogen.
Step-by-step explanation:
A 45-year-old woman who has never been pregnant is at an increased risk for increased risk of ovarian cancer (Option B). This is because fertility factors such as not having full-term pregnancies can influence the risk for various types of cancer, including ovarian and breast cancer. Women who have never been pregnant may have more ovulatory cycles, resulting in more exposure to estrogen, which can increase the risk for certain cancers. Additionally, older age can lead to a decline in fertility and hormonal changes that could impact cancer risk.