Assertion : Ernst Haeckel has classified living beings into three kingdoms.
Reason : The three kingdoms are Protista, Plantae and Animalia.

Options

A. If both Assertion and Reason are true and the Reason is a correct explanation of the Assertion.
B. If both Assertion and Reason are true but Reason is not a correct explantion of the Assertion.
C. If Assertion is ture but the Reason is false.
D. If both Assertion and Reason are false.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that Ernst Haeckel classified living beings into three kingdoms. This is a historical fact in biological classification.

2. **Understanding the Reason**: The reason provided states that the three kingdoms are Protista, Plantae, and Animalia. This aligns with Haeckel’s classification system, which indeed included these three kingdoms.

3. **Historical Context**: Ernst Haeckel proposed the three-kingdom system of classification in 1860. This system was significant as it expanded the understanding of living organisms beyond the traditional two-kingdom system (Plantae and Animalia).

4. **Details of Each Kingdom**:
- **Kingdom Protista**: This kingdom includes eukaryotic organisms that can be either autotrophic (able to produce their own food) or heterotrophic (dependent on other organisms for food).
- **Kingdom Plantae**: This kingdom consists of all plants, which are primarily autotrophic, meaning they produce their own food through photosynthesis.
- **Kingdom Animalia**: This kingdom includes eukaryotic and heterotrophic organisms, which rely on consuming other organisms for sustenance.

5. **Conclusion**: Since both the assertion and the reason are true and the reason correctly explains the assertion, the correct answer is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

**Final Answer**: Both the assertion and reason are true, and the reason is the correct explanation of the assertion.

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