In the following question, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as.
Assertion (A): Colloids are stable.
Reason (R): Brownian movement has a stirring effect, which does not allow the particles to settle.

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: Understand the Assertion (A)
The assertion states that "Colloids are stable."
- Colloids are mixtures where very small particles of one substance are dispersed throughout another substance.
- They are indeed stable because the dispersed particles do not settle out under the influence of gravity, which is a characteristic of colloidal systems.

### Step 2: Understand the Reason (R)
The reason states that "Brownian movement has a stirring effect, which does not allow the particles to settle."
- Brownian movement refers to the random motion of particles suspended in a fluid (liquid or gas) resulting from their collision with fast-moving molecules in the fluid.
- This random motion helps to keep the colloidal particles suspended and prevents them from settling due to gravity.

### Step 3: Analyze the Relationship Between A and R
- The assertion is true because colloids are stable.
- The reason is also true because Brownian movement does indeed prevent the particles from settling.
- Furthermore, the reason provides a valid explanation for the assertion, as it describes the mechanism (Brownian movement) that contributes to the stability of colloids.

### Conclusion
Both the assertion and the reason are true, and the reason correctly explains the assertion. Therefore, the correct choice is:

**Option 1: Both A and R are true, and R is the correct explanation of A.**

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