Assertion `:` In joint diastole, all the four chamber of heart are in relaxed state.
Reason `:` The tricuspid and bicuspid valves are open and semilunar valves are closed at this stage.

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion .
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
C. If Assertion is True but the Reason is False.
D. If both Assertion & Reason are false.

Answer

To solve the assertion-reason question, let's break it down step by step.

### Step 1: Understand the Assertion
The assertion states that "In joint diastole, all the four chambers of the heart are in a relaxed state."
- **Explanation**: Joint diastole refers to the phase of the cardiac cycle when both the atria and ventricles are relaxed, allowing the heart to fill with blood.

### Step 2: Understand the Reason
The reason states that "The tricuspid and bicuspid valves are open and semilunar valves are closed at this stage."
- **Explanation**: During joint diastole, the heart chambers are relaxed, which allows the atrioventricular (AV) valves (tricuspid and bicuspid) to open. This enables blood to flow from the atria into the ventricles. The semilunar valves (which lead to the aorta and pulmonary artery) are closed during this phase to prevent backflow of blood into the ventricles.

### Step 3: Analyze the Relationship Between Assertion and Reason
- Both the assertion and the reason are true statements regarding the cardiac cycle.
- The reason correctly describes the state of the heart during joint diastole, but it does not fully explain why all chambers are relaxed.

### Step 4: Conclusion
Since both the assertion and the reason are true, but the reason does not provide a correct explanation for the assertion, the correct answer is:
- **Option 2**: Both assertion and reason are true, but the reason is not a correct explanation of the assertion.