Assertion(A): A catalyst speed up a reaction but does not participate in its mechanism.
Reason(R): A catalyst provides an alternative path of lower activation energy to the reactants.

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 analyze the given assertion and reason regarding catalysts, we can break down the solution into the following steps:

### Step 1: Understand the Assertion
The assertion states that "A catalyst speeds up a reaction but does not participate in its mechanism." This means that while a catalyst increases the rate of a chemical reaction, it does not undergo any permanent change itself during the reaction process.

### Step 2: Understand the Reason
The reason provided is "A catalyst provides an alternative path of lower activation energy to the reactants." This indicates that a catalyst works by lowering the activation energy required for the reaction to occur, thus allowing the reaction to proceed more quickly.

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