The main systemic arteries branch off of the

Correct Answer: B

Rationale: The aorta (B) is the main systemic artery, branching into all major systemic arteries. Coronary (A), subclavian (C), and carotid (D) are its branches.

Correct Answer: B

Rationale: CCU typically means coronary care unit (B), specialized for heart conditions like MI. A and D are similar but less specific, C is unrelated.

Correct Answer: D

Rationale: Cardiac output = heart rate × stroke volume (D, ~5 L/min). A, B, and C are incorrect combinations.

Correct Answer: C

Rationale: Cardiac output (L/min) ÷ heart rate (bpm) = stroke volume (L/beat, C, ~70 ml). Efficiency (A) and index (B) are different, pressure (D) is unrelated.

Correct Answer: C

Rationale: The dicrotic notch (C) reflects aortic valve closure, causing a brief pressure dip. Pulmonary valve (A) is pulmonary, filling (B) is diastolic, contraction (D) is systolic.