Assertion : In a chemical engineering process, it is necessary to prepare sterile ambience.
Reason : Sterile ambience inhibits the growth of undesirable microbes during manufacture of product like antibiotics, vaccines and enzymes.

Options

A. a) Both assertion and reason are true and reason is correct explanation of assertion.
B. b) Both assertion and reason are true but reason is not correct explanation for assertion.
C. c) Assertion is true but reason is false.
D. d) Assertion is false but reason is true.

Explanation

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that in a chemical engineering process, it is necessary to prepare a sterile ambience. This means that the environment must be free from any microorganisms.

2. **Understanding the Reason**: The reason given is that a sterile ambience inhibits the growth of undesirable microbes during the manufacture of products like antibiotics, vaccines, and enzymes. This highlights the importance of maintaining sterility to prevent contamination.

3. **Evaluating the Assertion**: The assertion is true because a sterile environment is essential in chemical engineering processes, especially when producing sensitive products that can be easily contaminated.

4. **Evaluating the Reason**: The reason is also true. A sterile environment is crucial for inhibiting the growth of unwanted microbes, which could compromise the quality and safety of the products being manufactured.

5. **Connecting Assertion and Reason**: Since both the assertion and the reason are true, and the reason correctly explains why a sterile ambience is necessary in chemical engineering processes, we can conclude that the reason supports the assertion.

6. **Choosing the Correct Option**: Based on the evaluations, the correct answer is:
- Option A: Both assertion and reason are true, and the reason is the correct explanation of the assertion.

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

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