Correct Answer: C

Rationale: The correct answer is C: Chest radiography. In cases of acute abdomen, a chest radiograph is essential to rule out conditions like pneumothorax, pleural effusion, or pneumonia which may present with similar symptoms. This helps in identifying potential causes of abdominal pain outside the abdomen. Abdominal radiograph (A) may not provide enough information for diagnosis. Contrast radiography (B) and ultrasonography (D) are not universally essential for all cases of acute abdomen and may not be appropriate in certain situations.

Correct Answer: B

Rationale: The correct answer is B: Acute epidural hematoma. A crescent-shaped fluid collection seen on a head CT scan following trauma is indicative of an epidural hematoma, which typically occurs due to an arterial bleed between the dura mater and the skull. This collection appears biconvex due to the restriction of the hematoma by the dura mater and is often associated with a lucid interval followed by rapid deterioration. Explanation for Incorrect Choices: A: Acute subdural hematoma typically presents as a crescent-shaped collection but is located between the dura mater and arachnoid mater, not between the dura mater and skull as seen in epidural hematomas. C: Acute uncal herniation involves displacement of the uncus of the temporal lobe, leading to compression of the brainstem, but it does not manifest as a crescent-shaped fluid collection. D: Acute brainstem compression does not typically present as a distinct crescent-shaped

Correct Answer: B

Rationale: The correct answer is B: Iron and folic acid. Diamorphic anemia is characterized by the presence of both microcytic and macrocytic red blood cells, which can be caused by a deficiency in both iron and folic acid. Iron deficiency leads to microcytic anemia, while folic acid deficiency results in macrocytic anemia. Thiamine deficiency (Choice A) primarily affects the nervous system and does not directly cause diamorphic anemia. Liver enzymes deficiency (Choice D) does not directly lead to diamorphic anemia. Folic acid and thiamine deficiency (Choice C) can cause individual types of anemia but not diamorphic anemia.

Correct Answer: C

Rationale: The correct answer is C because in obstructive shock due to a large pulmonary embolus, there is increased resistance to blood flow out of the right ventricle, leading to elevated right ventricular pressure. This causes a backup of blood into the pulmonary circulation, increasing left ventricular pressure. The increased left ventricular pressure results in decreased cardiac output as the left ventricle struggles to pump against the increased resistance. A: Elevated atrial and decreased ventricular pressures - This is incorrect as obstructive shock typically results in elevated ventricular pressures due to increased resistance. B: Elevated right-sided and decreased left-sided pressures - This is partially true, but C is a more complete answer that explains the consequences of these pressures on cardiac output. D: Elevated left ventricular pressure and decreased systemic vascular resistance - This is incorrect as obstructive shock leads to increased, not decreased, systemic vascular resistance due to the embolus obstructing blood flow.

Correct Answer: B

Rationale: The correct answer is B: FALSE. In preeclampsia, epigastric pain is typically associated with liver and/or HELLP syndrome, not hyperacidity. Hyperacidity is more commonly seen in conditions like gastritis or peptic ulcers. Therefore, severe epigastric pain in preeclampsia is not related to hyperacidity. Other choices are not applicable as they do not provide relevant information to the question.