Assertion: Elements and compound are the examples of pure substances.
Reason : The properties of a compound are different from those of its constituent elements.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not 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 "Elements and compounds are examples of pure substances."
- **Explanation**: Pure substances are materials that are composed of only one type of particle, which can be either atoms (in the case of elements) or molecules (in the case of compounds). Therefore, both elements (like oxygen, gold) and compounds (like water, sodium chloride) qualify as pure substances.

2. **Evaluating the Reason**: The reason given is "The properties of a compound are different from those of its constituent elements."
- **Explanation**: This statement is true. When elements combine to form a compound, the resulting compound has distinct physical and chemical properties that are different from those of the individual elements. For example, hydrogen and oxygen are gases, but when they combine to form water, it is a liquid with different properties.

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