Assertion : Balancing a chemical equation is important to study a chemical reaction.
Reason A balanced chemical equation tells about energy changes that take place.

Options

A. If both assertion and reason are time and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Explanation

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that "Balancing a chemical equation is important to study a chemical reaction." This is true because a balanced chemical equation provides a clear representation of the quantities of reactants and products involved in a reaction. It ensures that the law of conservation of mass is followed, meaning that the number of atoms of each element is the same on both sides of the equation.

2. **Understanding the Reason**: The reason given is that "A balanced chemical equation tells about energy changes that take place." This is also true. When a chemical equation is balanced, it can provide insights into the energy changes (like exothermic or endothermic reactions) that occur during the reaction. The coefficients in the balanced equation can help in calculating the energy changes associated with the reaction.

3. **Connecting Assertion and Reason**: Both the assertion and the reason are true and are related to each other. The importance of balancing a chemical equation lies not only in adhering to the law of conservation of mass but also in understanding the energy dynamics of the reaction.

4. **Conclusion**: Since both the assertion and the reason are true and the reason supports the assertion, we can conclude that the statement is correct.

### Final Answer:
Both the assertion and the reason are true, and the reason supports the assertion.

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