Assertion (A): Both pepsin and rennin can simplify milk protein.
Reason (R): Pepsin and rennin are protein digesting enzymes.

Explanation

To analyze the assertion and reason provided in the question, we can break down the statements and evaluate their validity step by step.

### Step 1: Understand the Assertion (A)
The assertion states that "Both pepsin and rennin can simplify milk protein."

- **Evaluation**: Pepsin is an enzyme that primarily digests proteins in general, but it is not specifically effective at digesting milk protein (casein). Rennin, on the other hand, is specifically known for its ability to curdle and digest milk protein. Therefore, the assertion is **incorrect** because it implies that both enzymes can simplify milk protein, which is not true.

### Step 2: Understand the Reason (R)
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