Assertion: A reaction cannot become fast by itself unless a catalyst is added.
Reason: A catalyst always increases the speed of a reaction.
(a)If both (A) and (R) are correct, and (R) is the correct explanation of (A)
(b)If both (A) and (R) are correct, but (R) is the correct explanation of (A).
(c)If (A) is correct, but (R) is incorrect.
(d)If (A) is incorrect, but (R) is correct.

Options

A. If both (A) and (R) are correct, and (R) is the correct explanation of (A)
B. If both (A) and (R) are correct, but (R) is the correct explanation of (A).
C. If (A) is correct, but (R) is incorrect.
D. If (A) is incorrect, but (R) is correct. S

Explanation

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

### Step 1: Analyze the Assertion
The assertion states: "A reaction cannot become fast by itself unless a catalyst is added."

- This statement implies that without a catalyst, a reaction cannot speed up. However, this is not entirely true. Reactions can increase in speed due to factors such as increased temperature, concentration of reactants, or pressure (in the case of gases). Therefore, the assertion is incorrect.

### Step 2: Analyze the Reason
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