The risk of developing infective endocarditis is the least in a patient with:

Correct Answer: D

Rationale: Large atrial septal defects do not cause turbulent flow near valves or endocardial surfaces, making them less prone to infective endocarditis compared to other defects like VSD, which promote bacterial seeding.

Correct Answer: C

Rationale: Smokeless tobacco use is strongly linked to cancers of the oral cavity and esophagus.

Correct Answer: C

Rationale: Severe aortic stenosis impairs cardiac output, leading to reduced perfusion and obstructive shock, unlike conditions like myocarditis or dehydration.

Correct Answer: D

Rationale: Arsine gas causes massive hemolysis due to red blood cell destruction, leading to anemia and hemoglobinuria.

Correct Answer: A

Rationale: Preterm infants have underdeveloped lungs, and mechanical ventilation or high oxygen pressure can lead to alveolar rupture, causing air to accumulate in the pleural space (pneumothorax), leading to respiratory distress.