Final answer:
The nurse would be most concerned about a client who smokes cigarettes occasionally during pregnancy due to the associated health risks to the fetus, including reduced oxygen flow and developmental problems.
Step-by-step explanation:
The nurse in a prenatal clinic would be most concerned if a client states: c) I occasionally smoke a few cigarettes to manage stress. Smoking during pregnancy poses significant health risks to the fetus. It can result in reduced oxygen flow to the fetus, increase the risk of premature birth, low birth weight, and contribute to developmental problems. On the other hand, taking a prenatal vitamin with folic acid, enjoying moderate exercise like walking, and limiting caffeine intake are all beneficial or at least acceptable behaviors during pregnancy.
According to the Food and Nutrition Board of the Institute of Medicine, it is recommended that all women who might become pregnant consume at least 400 µg/day of folate from supplements or fortified foods to help prevent certain birth defects such as neural tube defects, which include conditions like spina bifida. Folic acid is crucial in the early stages of pregnancy for proper neural tube development.