When should iron supplementation during a normal pregnancy begin?
Correct Answer: D
Rationale: The correct answer is D: In the second trimester. During the second trimester, the demand for iron significantly increases due to the rapid growth of the fetus and expansion of maternal blood volume. This is the optimal time to begin iron supplementation to prevent iron deficiency anemia in both the mother and the developing baby. Starting iron supplementation in the first trimester may not be necessary as iron needs are not as high yet. Waiting until the third trimester may lead to insufficient time for iron stores to build up adequately. Beginning before pregnancy is not necessary unless the mother has pre-existing iron deficiency.