Assertion: Euglena is an organisms with a controversial position in classification of living organisms.
Reason: Euglena has parasitic nutrition.

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 assertion and reason question regarding Euglena, we will analyze both statements step by step.

### Step 1: Analyze the Assertion
**Assertion:** Euglena is an organism with a controversial position in classification of living organisms.

- **Explanation:** This statement is true. Euglena is a unicellular organism that exhibits characteristics of both plants and animals. It is classified under the kingdom Protista, which includes unicellular eukaryotes. The controversy arises because Euglena possesses chloroplasts and can perform photosynthesis like plants, but it can also exhibit heterotrophic behavior when light is not available.

### Step 2: Analyze the Reason
**Reason:** Euglena has parasitic nutrition.

- **Explanation:** This statement is false. Euglena does not have parasitic nutrition. Instead, it primarily exhibits photoautotrophic nutrition (photosynthesis) and can also adapt to a heterotrophic mode by consuming small microorganisms when light is absent. It does not derive its nutrition from a host organism, which is characteristic of parasitic organisms.

### Step 3: Conclusion
- The assertion is true, while the reason is false. Therefore, the correct relationship is that the assertion is correct, but the reason does not provide a valid explanation for the assertion.

### Final Answer
The correct option is that the assertion is true, and the reason is false.

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