Correct Answer: D

Rationale: The correct answer is D: Decreases blood pressure. Calcium channel blockers primarily work by relaxing the blood vessels, leading to a decrease in blood pressure. Choice A, 'Decreases heart rate,' is incorrect because calcium channel blockers do not significantly affect heart rate. Choice B, 'Increases heart rate,' is incorrect as calcium channel blockers do not have a primary effect of increasing heart rate. Choice C, 'Increases blood pressure,' is incorrect as the primary effect of calcium channel blockers is to decrease blood pressure by vasodilation.

Correct Answer: A

Rationale: Cardiomyopathy is the correct answer. In cardiomyopathy, the heart muscle becomes weak and cannot pump blood effectively, which can lead to heart failure. Myocarditis (choice B) is inflammation of the heart muscle, not specifically causing muscle weakness. Endocarditis (choice C) is an infection of the inner lining of the heart chambers and valves. Pericarditis (choice D) is inflammation of the pericardium, the outer lining of the heart.

Correct Answer: A

Rationale: Bronchoscopy is the correct answer because it is a procedure specifically designed to visualize the airways and diagnose lung diseases by allowing doctors to examine the inside of the airways. Thoracentesis involves the removal of fluid from the pleural space around the lungs, not the airways. Pulmonary function tests assess how well the lungs work but do not visualize the airways directly. A chest X-ray provides an image of the lungs and surrounding structures but does not involve direct visualization of the airways.

Correct Answer: A

Rationale: The correct answer is A: Cardiac output. Cardiac output is the volume of blood pumped by the heart per minute. It is calculated by multiplying the stroke volume (the amount of blood pumped out of the heart in each beat) by the heart rate (number of heartbeats per minute). This question specifically asks for the total amount of blood pumped through the circulatory system in a minute, which is represented by cardiac output. Choices B, C, and D are incorrect because stroke volume refers to the amount of blood pumped out of the heart in each beat, end-diastolic volume is the volume of blood in the heart at the end of diastole, and ejection fraction is the percentage of blood pumped out of the heart with each contraction, not the total amount pumped per minute.

Correct Answer: A

Rationale: The correct answer is A: Cough. Enalapril is an ACE inhibitor, and cough is a common side effect associated with this class of medication. Monitoring for cough is crucial as it can indicate the development of a potentially serious condition known as angioedema. Hyperkalemia (choice B) is a possible side effect of ACE inhibitors but is not the most important side effect to monitor. Hypotension (choice C) and dizziness (choice D) are also potential side effects of enalapril; however, cough takes precedence due to its association with angioedema, a severe adverse reaction.