Final answer:
The correct option is a.
In the first trimester of pregnancy, a woman typically gains between 2 - 4 pounds as there is no need for increased calorie consumption. This translates to about 1 pound per month. Later in pregnancy, weight gain increases as additional calories are needed to support fetal growth.
Step-by-step explanation:
A pregnant woman typically gains 2 - 4 pounds during the first trimester of her pregnancy. This weight gain is fairly modest because during this time, there is no need for additional calorie intake to maintain a healthy pregnancy.
On average, a weight gain of approximately 0.45 kg (1 lb) per month is common. As the pregnancy progresses into the second and third trimesters, the woman's appetite increases and it is recommended to consume an additional 300 calories per day to support the rapidly growing fetus.
Most women will then gain about 0.45 kg (1 lb) per week.