The recommended method of screening for overweight in children and adolescents is measuring the child's:

Choice A reason: Slowing the heart rate does not increase diastolic filling time. Diastolic filling time is the time during which the ventricles are relaxed and filling with blood. Slowing the heart rate would decrease the cardiac output and worsen the heart failure.

Choice B reason: Increasing urine output does decrease pulmonary congestion, but it is not the primary effect of Captopril. Captopril is an angiotensin-converting enzyme (ACE) inhibitor, which blocks the conversion of angiotensin I to angiotensin II, a potent vasoconstrictor. This reduces the blood pressure and the afterload on the heart. Diuretics are the drugs that increase urine output and reduce fluid overload.

Choice C reason: This is the correct choice. Decreasing the afterload means reducing the resistance that the heart has to overcome to pump blood to the body. This lowers the blood pressure and the workload on the heart, which improves the cardiac function and reduces the symptoms of heart failure.

Choice D reason: Increasing serum potassium does not improve cardiac performance. In fact, high levels of potassium can cause cardiac arrhythmias and cardiac arrest. Captopril can cause hyperkalemia (high potassium) as a side effect, which is why patients on this drug need to monitor their potassium levels and avoid potassium supplements or salt substitutes.

Choice A reason: This is the correct choice. Aspirin is a part of the treatment for children with Kawasaki disease, which is a rare but serious condition that causes inflammation of the blood vessels. Aspirin is given to reduce fever, inflammation, and the risk of developing coronary artery aneurysms. Aspirin is usually given in high doses during the acute phase of the disease and then in low doses as a preventive measure until the inflammation subsides.

Choice B reason: This is not a good choice. Aspirin is not contraindicated for children with Kawasaki disease, unlike other conditions such as Reye syndrome or viral infections. Aspirin is a beneficial and essential part of the treatment for children with Kawasaki disease, as it can prevent serious and potentially fatal complications.