A; living organisms can exist alone
R: A population is a group of organisms of entirely different species occupying a particular area.

Options

A. If both As and R are correct and R is correct explanation of As
B. If both As and R are correct but R is not correct explanation of As
C. If As is correct, R is wrong
D. If both As and R are wrong.

Answer

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Analyze the Assertion
The assertion states: "Living organisms can exist alone."
- This statement is **incorrect**. While some organisms can survive in isolation, most living organisms depend on others for resources such as food, water, and shelter. For example, plants need sunlight and nutrients from the soil, while animals often rely on other organisms for food.

### Step 2: Analyze the Reason
The reason states: "A population is a group of organisms of entirely different species occupying a particular area."
- This statement is also **incorrect**. A population is defined as a group of individuals of the same species living in a particular area. Different species living in the same area would be referred to as a community, not a population.

### Step 3: Conclusion
Since both the assertion and the reason are incorrect, we can conclude that the correct answer is option number 4: both assertion and reason are wrong.

### Final Answer
Both the assertion and the reason are incorrect.

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