A pregnancy of 6 weeks' gestation is confirmed in a moderately overweight patient. The patient asks the nurse practitioner, "Should I diet so I won't gain too much weight during this pregnancy?" The nurse practitioner appropriately responds:

O A - "It is probably a good idea to wait until the second trimester before initiating a diet for weight loss."
O B - "A weight gain of approximately 25 pounds is ideal for both you and baby."
O C - "It doesn't matter how much weight you gain or lose as long as you eat a well-balanced diet."
O D . "Just try to limit your weight gain as much as you are able."