The given list represents some facts about reforestation.
I. Reforestation can occur both naturally and also by human intervention.
II. Plants of the same species are planted in the forests.
III. Trees whose stumps are burnt down cannot be re-grown.
IV. The number of trees planted is equal to the number of trees cut from the forests.

Options

A. only I is incorrect
B. only II is incorrect
C. both I and III are incorrect
D. both II and IV are incorrect

Answer

To analyze the given statements about reforestation, we will evaluate each statement one by one.

### Step-by-Step Solution:

1. **Evaluate Statement I:**
- "Reforestation can occur both naturally and also by human intervention."
- This statement is **true**. Reforestation can happen naturally when trees regenerate on their own, and it can also be facilitated by humans who plant new trees.

2. **Evaluate Statement II:**
- "Plants of the same species are planted in the forests."
- This statement is **false**. In reforestation, it is common to plant a variety of species to promote biodiversity, not just the same species.

3. **Evaluate Statement III:**
- "Trees whose stumps are burnt down cannot be re-grown."
- This statement is **false**. Many trees can regenerate from their stumps if they are not completely destroyed. Some species can sprout new growth from the remaining stump.

4. **Evaluate Statement IV:**
- "The number of trees planted is equal to the number of trees cut from the forests."
- This statement is **true**. In sustainable reforestation practices, the goal is often to replace the number of trees that have been cut down with new plantings.

### Conclusion:
Based on the evaluations:
- Statement I: True
- Statement II: False
- Statement III: False
- Statement IV: True

The incorrect statements are II and III. Therefore, the correct answer is that both the second and third statements are incorrect.