The primary function of the stomach is:

Correct Answer: B

Rationale: The correct answer is B because the stomach's primary function is to store food, churn it to mix it with digestive enzymes, and begin the process of digestion. This is essential for breaking down food into smaller particles to facilitate nutrient absorption in the small intestine. Choice A is incorrect as the main organ for fat digestion is the small intestine. Choice C is incorrect as nutrient absorption primarily occurs in the small intestine. Choice D is incorrect as packaging feces is the role of the large intestine, not the stomach.

Correct Answer: C

Rationale: The most accurate statement is C: "Asthma is associated with breathlessness particularly on lying flat." This is correct because asthma symptoms often worsen when lying flat due to increased pressure on the chest and airways. Option A is incorrect because a long-acting beta2-agonist is not recommended for mild intermittent asthma as it is a step-up therapy for persistent asthma. Option B is incorrect as chronic productive cough is more commonly associated with conditions like chronic bronchitis. Option D is incorrect because a reversibility of <10% in FEV1 is not consistent with a diagnosis of asthma, as asthma typically shows significant reversibility in lung function tests.

Correct Answer: A

Rationale: Rationale: 1. Fasting plasma glucose >=7.0 mmol/l is a diagnostic criteria for diabetes. 2. It indicates sustained hyperglycaemia without food intake influencing the result. 3. Choice B tests glucose response to a glucose challenge and may not reflect fasting levels. 4. HbA1c measures average glucose levels over 2-3 months, not immediate status. 5. Choice D lacks specificity as random glucose levels can fluctuate.

Correct Answer: B

Rationale: The correct answer is B. Lowering blood pressure and urgent CT angiogram are crucial in suspected aortic dissection. High BP with variability between arms and tearing chest pain are classic signs. T-wave inversions in inferior leads may occur but are not specific to aortic dissection. Choice A is incorrect as antibiotics are not indicated unless infective endocarditis is confirmed. Choice C is incorrect as antiplatelet therapy and heparin are not first-line treatments for aortic dissection. Choice D is incorrect as NSAIDs can worsen aortic dissection, and echocardiogram is not the initial imaging modality of choice for this condition.

Correct Answer: D

Rationale: The correct answer is D: Measure gastric acid secretion. In a suspected case of gastrinoma, elevated serum gastrin levels can lead to increased gastric acid secretion. Measuring gastric acid secretion can help confirm the diagnosis of gastrinoma by assessing for increased acid production. This can be done with tests like the gastric acid stimulation test or the secretin stimulation test. Option A is incorrect as an exploratory laparotomy is an invasive procedure and should not be the first step in the diagnostic process. Option B, measuring serum gastrin in response to secretin infusion, may be helpful in confirming the diagnosis but measuring gastric acid secretion is more directly related to the pathophysiology of gastrinoma. Option C, treating for H. pylori, is not indicated in this case as the patient's symptoms are more suggestive of gastrinoma rather than H. pylori infection.