A : In nature all thermodynamic processes are irreversible.
R : During a thermodynamic process it is not possible to eliminate dissipative effects.

Options

A. If both Assertion & Reason are true and the reason is the correct explantion of the assertion, then mark(1)
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2).
C. If Assertion is true statement but Reason is false, then mark (3).
D. If both Assertion and Reason are false statements, then mark (4)

Answer

To analyze the statements given in the question, we will break down the assertion (A) and the reason (R) step by step.

### Step 1: Understanding the Assertion (A)
The assertion states: "In nature, all thermodynamic processes are irreversible."
- This statement is generally accepted in thermodynamics. In real-world scenarios, processes such as mixing, heat transfer, and expansion against a pressure are irreversible due to the presence of dissipative effects like friction, turbulence, and thermal conduction.

### Step 2: Understanding the Reason (R)
The reason states: "During a thermodynamic process, it is not possible to eliminate dissipative effects."
- This statement is also true. In natural processes, dissipative effects (like friction and heat loss) cannot be completely eliminated. These effects contribute to the irreversibility of processes.

### Step 3: Connecting Assertion and Reason
- The assertion (A) is that all thermodynamic processes in nature are irreversible, and the reason (R) explains why this is the case, stating that dissipative effects are inherently present in these processes.

### Step 4: Conclusion
- Since both the assertion and the reason are correct, and the reason provides a valid explanation for the assertion, we conclude that the answer is that both statements are true, and the reason explains the assertion.

### Final Answer
Both the assertion (A) and the reason (R) are correct, and the reason explains the assertion.

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