Semilunar valves open during the ventricular diastole.

Explanation

To solve the question regarding whether semilunar valves open during ventricular diastole, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Cardiac Cycle**: The cardiac cycle consists of two main phases: diastole and systole. Diastole is when the heart muscles relax, and systole is when the heart muscles contract.

2. **Identify the Role of Semilunar Valves**: The semilunar valves include the pulmonary valve and the aortic valve. These valves are located between the ventricles and the major arteries (pulmonary artery and aorta).

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