Assertion: The recombinant cells are multiplied in a continuous culture system
Reason :It is to maintain the cells in their physiologically most active log/exponential phase

Options

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

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "the recombinant cells are multiplied in a continuous culture system."
- This is true because continuous culture systems are designed to maintain and grow cells over extended periods, allowing for the production of recombinant proteins.

2. **Understanding the Reason**:
- The reason provided is that "it is to maintain the cells in their physiologically most active log/exponential phase."
- This is also true. The log or exponential phase is when cells are actively dividing and metabolically active, which is ideal for producing recombinant proteins.

3. **Connecting Assertion and Reason**:
- The assertion and reason are connected because the purpose of using a continuous culture system is indeed to keep the cells in their most active growth phase, which enhances productivity.

4. **Conclusion**:
- Both the assertion and the reason are true.
- The reason correctly explains why the assertion is true, as maintaining cells in the exponential phase is crucial for maximizing the yield of recombinant proteins.

### Final Answer:
Both the assertion and the reason are true, and the reason is the correct explanation of the assertion.

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