Cardiac Cycle Event Sequence

Steps:

• Identify key phases: atrial systole, ventricular systole, ejection, relaxation.
• Match letters to standard order: W (atrial systole), Y (isovolumetric contraction), X (ejection), V (isovolumetric relaxation).
• Eliminate sequences skipping or misordering phases.
• Verify C follows logical progression without gaps.

Why C is correct:

• C (W Y X V) aligns with the defined cardiac cycle: atrial systole (W) precedes ventricular contraction (Y), ejection (X), and relaxation (V), per physiological sequence.

Why the others are wrong:

• A skips critical contraction phase, jumping to depolarization prematurely.
• B includes undefined T early, disrupting ventricular systole order.
• D omits ejection and relaxation, incomplete for full cycle.

Not enough information on exact letter definitions, but C fits standard model.

Final answer: C