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 rupture of the uterine wall confined to the tissue. Extra-peritoneal uterine rupture refers to a rupture that does not breach the peritoneal cavity, keeping the damage confined to the uterine tissue only. This is distinct from intra-peritoneal rupture which involves the peritoneum (choice B) and complete rupture of all uterine layers (choice D). Choice A is incorrect as it does not specify the location of the tear, and it does not necessarily imply that there is no organ damage.

Correct Answer: A

Rationale: The correct answer is A: Wernicke's encephalopathy. Hyperemesis gravidarum is severe nausea and vomiting during pregnancy. Wernicke's encephalopathy is a neurological complication due to thiamine deficiency, which can occur in severe cases of vomiting, leading to impaired brain function. Sheehan's syndrome is a complication of postpartum pituitary necrosis. Maurice encephalitis is a fictional term not related to this context. Antepartum bleeding is not a typical complication of hyperemesis gravidarum. Therefore, the correct answer is A due to the potential neurological impact of severe vomiting on thiamine levels.

Correct Answer: D

Rationale: The correct answer is D because the main aims of an exchange transfusion procedure are to control haemolysis (process of breaking down red blood cells) and restore hemoglobin levels. This procedure involves removing the baby's blood and replacing it with donor blood to prevent complications from severe jaundice or other conditions. Choice A is incorrect because exchange transfusion does not necessarily cure haemolysis, but it helps control it. Choice B is incorrect as the procedure focuses on managing specific issues rather than removing all toxic materials. Choice C is incorrect because it does not directly address the primary goals of an exchange transfusion.

Correct Answer: D

Rationale: Step-by-step rationale for why choice D (Atelectasis) is correct: 1. Ascorbic acid deficiency can lead to impaired lung function, increasing the risk of atelectasis. 2. Anemia can cause decreased oxygen-carrying capacity, contributing to atelectasis. 3. Volume contraction can lead to reduced lung expansion, further predisposing to atelectasis. Summary: - Choice A (Prolonged intubation): Intubation duration is more related to respiratory complications, not directly linked to the mentioned risk factors. - Choice B (Thromboembolism): Risk factors like immobility and hypercoagulability are more relevant to thromboembolism. - Choice C (Delayed wound healing): More associated with factors like malnutrition and impaired immune function rather than the mentioned risk factors.