Assertion: That branch of science which deals with the study of living organisms is called Biology.
Reason: Living organisms always have cellular organisation, which may be unicellular or multicellular.

Options

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

Answer

To analyze the given assertion and reason, we will break down the information step by step.

### Step 1: Understand the Assertion
The assertion states that "the branch of science which deals with the study of living organisms is called Biology."
- This is a true statement. Biology is indeed the scientific study of life and living organisms.

### Step 2: Understand the Reason
The reason provided is that "living organisms always have cellular organization, which may be unicellular or multicellular."
- This statement is also true. All living organisms are made up of cells, which are the basic units of life. They can be unicellular (consisting of a single cell, like bacteria) or multicellular (consisting of multiple cells, like humans).

### Step 3: Evaluate the Relationship Between Assertion and Reason
While both the assertion and reason are true, we need to determine if the reason correctly explains the assertion.
- The assertion defines what Biology is, while the reason describes a characteristic of living organisms. The reason does not explain why the study of living organisms is called Biology.

### Step 4: Conclusion
Based on the evaluation:
- Both the assertion and the reason are correct statements.
- However, the reason does not serve as a correct explanation for the assertion.

Thus, the conclusion is that the correct option is: **Both assertion and reason are correct, but the reason is not the correct explanation of the assertion.**

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