Assertion (A): Unicellular eukaryotes come under the kingdom protista.
Reason (R) : Mode of nutrition can be autotrophic or heterotrophic

Options

A. Both A and R are true, but R is the correct explanation for A.
B. Both A and R are true, but R is the not the correct explanation for A.
C. A is true and R is false.
D. A is false and R is true.

Explanation

To analyze the assertion and reason provided in the question, we will break it down step by step.

### Step 1: Understand the Assertion (A)
The assertion states that "Unicellular eukaryotes come under the kingdom Protista."
- **Explanation**: Unicellular eukaryotes are organisms that consist of a single cell and have a defined nucleus and organelles. The kingdom Protista is known for containing a diverse group of mostly unicellular organisms, including protozoa and some algae.

### Step 2: Understand the Reason (R)
The reason states that "Mode of nutrition can be autotrophic or heterotrophic."
- **Explanation**: Autotrophic organisms can produce their own food through processes like photosynthesis (e.g., some algae), while heterotrophic organisms obtain their food by consuming other organisms (e.g., protozoa). This characteristic of having varied modes of nutrition is indeed true for many protists.

### Step 3: Evaluate the Relationship Between Assertion and Reason
Now, we need to determine if the reason supports the assertion.
- **Analysis**: The assertion is correct as unicellular eukaryotes are classified under the kingdom Protista. The reason is also correct as many protists exhibit both autotrophic and heterotrophic modes of nutrition. However, the reason does not directly support the assertion; it simply describes a characteristic of the organisms in that kingdom.

### Conclusion
Both the assertion and the reason are true, but the reason does not provide a justification for the assertion. Therefore, the correct conclusion is:
- **Assertion (A) is true.**
- **Reason (R) is true, but it does not support Assertion (A).**

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