How many of the given statements are incorrect ?
I. The Universe is almost 20 billion years old.
II. Analogy indicates common ancestry.
III. When adaptive radiation has occurred in an isolated geographical area, one can call this convergent evolution.
IV. Natural selection is based on certain observations which are factual.
V. Hardy-Weinberg principle says that allele frequencies in area are unstable.

Options

A. Two
B. Three
C. One
D. Four

Answer

To determine how many of the given statements are incorrect, let's analyze each statement one by one:

### Step-by-Step Solution:

1. **Statement I: The Universe is almost 20 billion years old.**
- **Analysis**: The current scientific consensus is that the Universe is approximately 13.7 billion years old. Therefore, this statement is incorrect.
- **Conclusion**: Incorrect.

2. **Statement II: Analogy indicates common ancestry.**
- **Analysis**: Analogy refers to similarities in function between structures that arise from different evolutionary origins (e.g., wings of bats and birds). This does not indicate common ancestry; rather, it indicates convergent evolution. Thus, this statement is also incorrect.
- **Conclusion**: Incorrect.

3. **Statement III: When adaptive radiation has occurred in an isolated geographical area, one can call this convergent evolution.**
- **Analysis**: Adaptive radiation involves the diversification of a species into different forms to adapt to various environments, while convergent evolution refers to different species developing similar traits due to similar environmental pressures. These are distinct processes. Therefore, this statement is incorrect.
- **Conclusion**: Incorrect.

4. **Statement IV: Natural selection is based on certain observations which are factual.**
- **Analysis**: Natural selection is indeed based on factual observations regarding the survival and reproduction of organisms in their environments. This statement is correct.
- **Conclusion**: Correct.

5. **Statement V: Hardy-Weinberg principle says that allele frequencies in an area are unstable.**
- **Analysis**: The Hardy-Weinberg principle states that allele frequencies in a population remain constant from generation to generation in the absence of evolutionary influences. Therefore, this statement is incorrect.
- **Conclusion**: Incorrect.

### Summary of Findings:
- **Incorrect Statements**: I, II, III, and V.
- **Total Incorrect Statements**: 4

### Final Answer:
**There are 4 incorrect statements.**

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