Correct Answer: C

Rationale: The correct answer is C: Occipito-posterior. This position occurs when the baby's head is facing forward but towards the mother's spine. This position can cause intense back pain during labor because the baby's head puts pressure on the mother's lower back. Occipito-anterior (A) is the most common and ideal position for labor. Transverse position (B) is when the baby is lying sideways, which may cause prolonged labor but not necessarily intense back pain. Occipito-lateral (D) is a less common position where the baby's head is facing sideways, which may not specifically cause intense back pain.

Correct Answer: A

Rationale: The correct answer is A: Prevent alveoli of the lungs from collapsing. Surfactant reduces surface tension in the alveoli, preventing them from collapsing during exhalation and maintaining lung compliance. B, C, and D are incorrect because surfactant primarily affects lung mechanics, not the initiation of breathing, maturity of the respiratory center, or immediate regulation of breathing upon birth.

Correct Answer: A

Rationale: The engaging diameter in a face presentation is the sub-mento vertical diameter. This is the correct answer because it represents the distance from the tip of the chin (mentum) to the highest point on the skull (vertex), which is the most critical diameter for the face to descend through the pelvis during childbirth. Choice B (Sub-mento bregmatic diameter) is incorrect because it represents the distance from the tip of the chin to the anterior fontanelle, not the highest point on the skull. Choice C (Mento vertical diameter) is incorrect because it refers to the distance from the chin to the base of the skull, not the highest point on the skull. Choice D (Sub-occipito bregmatic diameter) is incorrect because it represents the distance from the base of the skull to the anterior fontanelle, not involving the chin.

Correct Answer: C

Rationale: The correct answer is C: A long history of alcohol use. In this case, the patient T. S. is brain dead following a catastrophic accident. Although she had an organ donor notation, her long history of alcohol use precludes her from serving as a liver donor. Chronic alcohol use can lead to liver damage and compromise the quality of the liver for transplantation. Encephalopathy (choice A) is a potential complication of liver disease, but it does not preclude her from being a liver donor. Hepatitis C infection (choice B) and biliary cirrhosis (choice D) may affect the liver, but they do not automatically disqualify her as a donor.

Correct Answer: B

Rationale: Postdatism refers to a pregnancy that extends beyond the normal gestation period of 280 days. The correct answer is B (294 days) as it is more than the standard 280-day term. Choice A (280 days) is the normal term, not postdatism. Choices C (290 days) and D (287 days) are also below the 294-day mark, making them incorrect for defining postdatism.