Assertion : A protein is a heteropolymer.
Reason : Dietary proteins are the source of non-essential amino acids.

A : If both Assertion and Reason are true and the Reason is a correct explanation of the Assertion.
B: If both Assertion and 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 and Reason are false.

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Analyze the Assertion
The assertion states: "A protein is a heteropolymer."
- A heteropolymer is a polymer made up of different types of monomers. In the case of proteins, they are made up of 20 different amino acids (the monomers). Therefore, this statement is true.

### Step 2: Analyze the Reason
The reason states: "Dietary proteins are the source of non-essential amino acids."
- Non-essential amino acids are those that the body can synthesize on its own. While dietary proteins do provide essential amino acids, which the body cannot synthesize, they do not serve as a direct source of non-essential amino acids because these are produced by the body itself from the essential amino acids. Thus, this statement is false.

### Step 3: Conclusion
- Since the assertion is true and the reason is false, the correct answer is option C: "If Assertion is true but the Reason is false."

### Final Answer:
C: If Assertion is true but the Reason is false.

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