Assertion (A): Population has certain attributes which an individual organism does not have.
Reason (R): Population is a groups of people living in well defined area, at a particular time.

Options

A. Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A)
B. Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A)
C. Assertion (A) is true but reason (R) is false.
D. Assertion (A) is false but reason (R) is true.

Explanation

To analyze the given assertion and reason, we will break down the statements and evaluate their truthfulness and relationship.

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that "Population has certain attributes which an individual organism does not have."
- This is true because populations exhibit characteristics such as birth rate, death rate, age distribution, and sex ratio, which cannot be applied to a single individual. For example, while an individual can be classified as male or female, a population can be described by its sex ratio (the ratio of males to females).

2. **Understanding the Reason (R)**:
- The reason states that "Population is a group of people living in a well-defined area, at a particular time."
- This statement is also true. A population is defined as a group of individuals of the same species that live in a specific area at a specific time. This definition is fundamental in ecology and population biology.

3. **Evaluating the Relationship**:
- Both the assertion and the reason are true.
- However, the reason does not serve as a correct explanation for the assertion. The assertion discusses the attributes of populations, while the reason merely defines what a population is without explaining why populations have attributes that individuals do not.

4. **Conclusion**:
- Therefore, both statements are true, but the reason is not the correct explanation of the assertion.

### Final Answer:
Both A and R are true, but R is not the correct explanation of A.

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