Correct Answer: B

Rationale: The correct answer is B. Acquired aplastic anemia in children is often caused by exposure to certain drugs, such as chloramphenicol or antiepileptics, which can lead to bone marrow failure and a decrease in all types of blood cells. Choices A, C, and D are incorrect because aplastic anemia is not commonly caused by deficient diet, congenital defects, or injury in children.

Correct Answer: B

Rationale: A neonate normally loses about 10% of the birth weight by age 3 to 4 days. The birth weight is usually regained by the 10th day of life. In this case, the weight loss from 3400 g to 3147 g is within the expected range. Therefore, the most appropriate action is to explain to the mother that this weight loss is within normal limits. Choice A is incorrect because supplemental feedings of formula are not indicated for this expected weight loss in a breastfed newborn. Choice C is incorrect as there is no evidence to suggest excessive weight loss at this point. Choice D is unnecessary at this stage and may not align with the current situation of normal weight loss post-birth.

Correct Answer: B

Rationale: At 2 months, infants typically react to loud noises with the Moro reflex, a startle response that is normal at this stage of development.

Correct Answer: D

Rationale: Colic is characterized by episodes of loud, inconsolable crying, often due to abdominal discomfort, and typically occurs in infants younger than 6 months. It is not related to poor mothering, nor does it necessarily result in weight loss.

Correct Answer: B

Rationale: Being persistent through 10 to 15 minutes of food refusal is recommended to help increase caloric intake in infants with FTT. Establishing a routine and using developmental stimulation can also be helpful, but the priority is ensuring adequate caloric intake.