A : Polypropylene is an addition polymer.
R:Addition polymerization occurs among molecules which contain double bonds.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation 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 the mark 4.

Answer

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

### Step 1: Understand the Assertion
The assertion states that "Polypropylene is an addition polymer."

- **Explanation**: Polypropylene is indeed classified as an addition polymer. Addition polymers are formed through the process of addition polymerization, where monomer units with double bonds (unsaturated compounds) join together without the loss of any small molecules.

### Step 2: Understand the Reason
The reason states that "Addition polymerization occurs among molecules which contain double bonds."

- **Explanation**: This statement is correct. Addition polymerization specifically involves unsaturated monomers, which contain double or triple bonds. These bonds open up during the polymerization process, allowing the monomers to link together to form a polymer.

### Step 3: Analyze the Relationship Between Assertion and Reason
Now, we need to determine if the reason provides a correct explanation for the assertion.

- **Connection**: Since polypropylene is formed from propylene, which has a double bond, it fits the criteria for addition polymerization. Therefore, the reason explains why polypropylene is classified as an addition polymer.

### Conclusion
Both the assertion and the reason are true, and the reason correctly explains the assertion. Therefore, the answer to the question is:

**Both Assertion and Reason are true, and the Reason is the correct explanation for the Assertion.**

### Final Answer
The correct option is: Both A and R are true, and R is the correct explanation of A.

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