Which one of the following is a wrong statement ?

Options

A. Most of the forests have been lost in tropical areas.
B. Ozone in upper part of atmosphere is harmful to animals .
C. Greenhouse effect is a natural phenomenon
D. Eutrophication is a natural phenomenon in freshwater bodies.

Answer

To solve the question of identifying the wrong statement among the given options, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Understanding Deforestation:**
- The first statement mentions that most of the forests have been lost in tropical areas.
- Deforestation refers to the conversion of forested areas into non-forested ones.
- It is a well-documented fact that a significant percentage of forests, approximately 40%, have been lost in tropical regions due to various human activities.
- **Conclusion:** This statement is **correct**.

2. **Analyzing Ozone in the Atmosphere:**
- The second statement claims that ozone in the upper part of the atmosphere is harmful to animals.
- Ozone in the stratosphere (upper atmosphere) is known as "good ozone" and serves to protect living organisms from harmful ultraviolet (UV) radiation.
- Therefore, this statement is **incorrect** as it misrepresents the role of stratospheric ozone.
- **Conclusion:** This statement is **wrong**.

3. **Understanding the Greenhouse Effect:**
- The third statement asserts that the greenhouse effect is a natural phenomenon.
- The greenhouse effect is indeed a natural process that warms the Earth’s surface. It occurs when the sun's energy reaches the Earth and is reflected back to space, but some of it is trapped by greenhouse gases in the atmosphere.
- **Conclusion:** This statement is **correct**.

4. **Evaluating Eutrophication:**
- The fourth statement states that eutrophication is a natural phenomenon in freshwater bodies.
- Eutrophication refers to the process where water bodies become enriched with nutrients (like nitrogen and phosphorus), leading to excessive growth of algae and subsequent depletion of oxygen. This process can be natural, but it is often accelerated by human activities (e.g., agricultural runoff).
- **Conclusion:** This statement is generally considered **correct**, although it can be influenced by anthropogenic factors.

### Final Conclusion:
Based on the analysis, the **wrong statement** among the options provided is the second statement regarding ozone in the upper atmosphere.