The Ventricles are relaxed and the Ventricular pressure falls causing the closure of semilunar valves. These events are related to .

Options

A. atrial depolarization
B. ventricular systole
C. ventricular diastole
D. joint diastole

Answer

To solve the question regarding the relationship between the relaxation of the ventricles, the fall in ventricular pressure, and the closure of the semilunar valves, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Cardiac Cycle**: The cardiac cycle consists of various phases, including systole (contraction) and diastole (relaxation). It is important to know what happens during each phase.

2. **Identify the Phases**:
- **Atrial Depolarization**: This phase involves the contraction of the atria, pushing blood into the ventricles. This is not the phase where the ventricles are relaxed.
- **Ventricular Systole**: This is when the ventricles contract to pump blood out of the heart. During this phase, the ventricles are not relaxed, so this option is also incorrect.
- **Ventricular Diastole**: This is the phase where the ventricles relax, and the pressure within them falls. During this time, the semilunar valves close to prevent backflow of blood from the arteries into the ventricles.

3. **Conclusion**: Since the question describes a scenario where the ventricles are relaxed, the pressure is falling, and the semilunar valves are closing, this corresponds to the **Ventricular Diastole** phase of the cardiac cycle.

4. **Final Answer**: The events described in the question are related to **Ventricular Diastole**.