Blood pressure is highest right after ventricular contraction.

Steps:

• Blood enters the right atrium from veins at low pressure.
• Ventricles fill, then contract to pump blood into arteries.
• Left ventricle ejects blood into the aorta with greatest force.
• Pressure drops progressively through arteries, capillaries, and veins.

Why C is correct:

• Point C is in the aorta, where systolic pressure peaks due to left ventricular ejection (normal ~120 mmHg).

Why the others are wrong:

• A: Vena cava carries deoxygenated blood back at low venous pressure (~5 mmHg).
• B: Pulmonary artery receives blood from right ventricle at lower pressure (~25 mmHg).
• D: Pulmonary vein returns oxygenated blood to left atrium at low pressure (~10 mmHg).

Final answer: C