Assertion (A): A chemical reaction becomes faster at higher temperatures.
Reason (R): At higher temperatures, molecular motion becomes more rapid.

Options

A. Both A and R are true and R is the correct explanation of A.
B. Both A and R are true but R is NOT the correct explanation of A.
C. A is true but R is false.
D. A is false and R is true.

Explanation

To solve the assertion and reason question, we will analyze both statements step by step.

### Step 1: Analyze the Assertion (A)
**Assertion (A): A chemical reaction becomes faster at higher temperatures.**

- **Explanation**: In chemistry, it is well-established that increasing the temperature of a reaction generally increases the rate of that reaction. This is because higher temperatures provide more energy to the reactant molecules, allowing them to collide more frequently and with greater energy.

### Step 2: Analyze the Reason (R)
**Reason (R): At higher temperatures, molecular motion becomes more rapid.**

- **Explanation**: As temperature increases, the kinetic energy of the molecules also increases. This means that the molecules move faster and collide more often. The increased frequency and energy of collisions lead to a higher probability of successful reactions occurring.

### Step 3: Conclusion
- Both the assertion and the reason are true. The reason provided (R) correctly explains why the assertion (A) is true. Therefore, we can conclude that both A and R are true, and R is the correct explanation of A.

### Final Answer
Both Assertion (A) and Reason (R) are true, and R is the correct explanation of A.

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