Assertion; Biosphere is a closed system
!Reason; Closed vascular bundles are having intrafascicular cambium.

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

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that "Biosphere is a closed system."
- To evaluate this, we need to understand what the biosphere is. The biosphere is the part of Earth where life exists, encompassing all living organisms and their interactions with the environment.

2. **Defining a Closed System:**
- A closed system is defined as a system that does not exchange matter with its surroundings but can exchange energy.
- In the context of the Earth, it primarily receives energy from the sun while maintaining a constant mass, as there is no significant exchange of matter with outer space.

3. **Evaluating the Biosphere:**
- Since the biosphere is part of the Earth, which is considered a closed system (in terms of matter), the biosphere can also be classified as a closed system.
- Therefore, the assertion that the "Biosphere is a closed system" is **correct**.

4. **Understanding the Reason:**
- The reason states, "Closed vascular bundles are having intrafascicular cambium."
- Closed vascular bundles are structures found in certain plants, specifically in dicotyledons. They do not contain cambium, which is a layer of tissue responsible for secondary growth.

5. **Evaluating the Reason:**
- Since closed vascular bundles do not have cambium, the statement in the reason is **incorrect**.

6. **Conclusion:**
- The assertion is correct, while the reason is incorrect. Therefore, the correct answer is: **Assertion is correct, Reason is incorrect.**

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