Assertion: Autotrophic bacteria obtain their carbon from inorganic carbon.
Reason: Plants that obtain their energy from sunlight are called autotrophs.

Options

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

Answer

To analyze the given assertion and reason, we will break down the statements and evaluate their validity step by step.

### Step 1: Understand the Assertion
The assertion states: "Autotrophic bacteria obtain their carbon from inorganic carbon."
- Autotrophic bacteria are organisms that can produce their own food using inorganic substances.
- They typically use carbon dioxide (CO2), which is an inorganic carbon source, to synthesize organic compounds through processes such as photosynthesis or chemosynthesis.

**Conclusion for Step 1:** The assertion is true because autotrophic bacteria do indeed obtain their carbon from inorganic carbon sources like CO2.

### Step 2: Understand the Reason
The reason states: "Plants that obtain their energy from sunlight are called autotrophs."
- Autotrophs are organisms that can produce their own food.
- Plants are a primary example of autotrophs as they use sunlight, water, and carbon dioxide to produce glucose and oxygen through photosynthesis.

**Conclusion for Step 2:** The reason is also true because plants are classified as autotrophs due to their ability to use sunlight for energy.

### Step 3: Evaluate the Relationship Between Assertion and Reason
Now we need to determine if the reason provided is a correct explanation of the assertion.
- The assertion discusses autotrophic bacteria and their source of carbon.
- The reason discusses plants and their energy source.

**Conclusion for Step 3:** While both statements are true, the reason does not explain the assertion. The assertion is specific to bacteria, while the reason pertains to plants, making them unrelated in terms of explanation.

### Final Conclusion
Based on the evaluations:
- Both the assertion and reason are true.
- However, the reason does not explain the assertion.

Thus, the correct answer is: **Both A and R are true, but R is not the correct explanation of A.**

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