In the following question, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as.
Assertion (A): An ordinary filter paper impregnated with collodion solution stops the flow of colloidal particles.
Reason (R): Pore size of the filter paper becomes more than the size of colloidal particle.

Options

A. Both A and Rare true and R is the correct explanation of A
B. Both A and R are true but explanation of A
C. A is true but R is false
D. A is false and R is True

Explanation

To solve the question, we need to analyze both the Assertion (A) and the Reason (R) provided.

### Step 1: Understanding the Assertion (A)
The assertion states that "An ordinary filter paper impregnated with collodion solution stops the flow of colloidal particles."
- This means that when a colloidal solution is passed through this filter paper, the flow of colloidal particles is halted.

### Step 2: Evaluating the Reason (R)
The reason given is "Pore size of the filter paper becomes more than the size of colloidal particles."
- This implies that the filter paper's pores are larger than the colloidal particles, which would allow the particles to pass through.

### Step 3: Analyzing the Relationship
- For the assertion to be true, the filter paper must have pores that are smaller than the colloidal particles. If the pores are larger, the colloidal particles would not be stopped, contradicting the assertion.
- Therefore, the assertion is true because the filter paper can indeed stop the flow of colloidal particles due to its pore size being smaller than that of the colloidal particles.
- The reason is false because it incorrectly states that the pore size is larger than the size of colloidal particles.

### Conclusion
- The assertion (A) is true, and the reason (R) is false. Thus, the correct choice is that Assertion A is true, but Reason R is false.

### Final Answer
The answer is: Assertion (A) is true, Reason (R) is false.

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