Correct Answer: B

Rationale: Step 1: Hyperemesis gravidarum is characterized by severe nausea and vomiting during pregnancy. Step 2: Inability to eat or retain food all through is a hallmark feature due to excessive vomiting. Step 3: This leads to dehydration, electrolyte imbalances, and weight loss. Step 4: Pallor, cyanosis, weakness, and smaller fundal height are not specific to hyperemesis gravidarum. Summary: Choice B is correct as it directly relates to the primary symptom of excessive vomiting in hyperemesis gravidarum, while the other choices are not specific to this condition.

Correct Answer: A

Rationale: The correct answer is A because folic acid supplementation plays a crucial role in promoting spinal cord closure during fetal development, preventing neural tube defects. Folic acid helps in the formation of neural tube structures, ensuring proper closure and preventing defects like spina bifida. Choices B, C, and D are incorrect as preventing infections, enhancing fetal growth, and regulating blood sugar levels are not direct mechanisms through which folic acid prevents neural tube defects.

Correct Answer: B

Rationale: The correct answer is B: Grunting on expiration. In respiratory distress syndrome, the infant may exhibit grunting on expiration due to the difficulty in maintaining lung inflation during exhalation. This is a compensatory mechanism to increase functional residual capacity. Grunting on inspiration (choice A) may be seen in other respiratory conditions. Flaring of the nostrils (choice C) is a sign of increased work of breathing but is not specific to respiratory distress syndrome. Neonatal tachycardia (choice D) can be a nonspecific sign of distress and is not a specific feature of respiratory distress syndrome.

Correct Answer: A

Rationale: The correct answer is A because occipito-posterior position can lead to prolonged labor due to poor fetal positioning, causing maternal back pain. This can result in fetal distress as the baby may have difficulty descending through the birth canal. Postpartum hemorrhage, uterine rupture, fetal death (choices B and C) are not typically associated with occipito-posterior position. Therefore, choice A is the most appropriate answer.

Correct Answer: D

Rationale: The correct answer is D because exchange transfusion aims to control hemolysis by removing the damaged red blood cells and replacing them with healthy ones, thus restoring hemoglobin levels. This procedure does not cure haemolysis or hypoxia entirely, nor does it stabilize the immune system or liver functions. It specifically targets controlling hemolysis and restoring hemoglobin levels to improve the patient's condition.