The bones of forelimbs of whale, bat, cheetah and man are similar in structure, because.

Options

A. one organism have given rise to another
B. they share a common ancestor
C. they perform the same function
D. the have biochemical similarities

Explanation

**Step-by-Step Solution:**

1. **Understanding Homologous Structures**: The first step is to define what homologous structures are. Homologous structures are anatomical features in different species that share a similar structural origin but may serve different functions.

2. **Identifying the Forelimbs**: The forelimbs of the whale, bat, cheetah, and man are examples of homologous structures. Despite their different functions, they share a common structural framework.

3. **Analyzing the Functions**:
- The forelimb of a whale is adapted for swimming.
- The forelimb of a bat is adapted for flying.
- The forelimb of a cheetah is adapted for running.
- The forelimb of a man is adapted for walking and manipulation.

4. **Conclusion**: The similarity in structure among these forelimbs arises from a common evolutionary ancestor, which is why they are classified as homologous. The differences in function highlight the concept of adaptive radiation, where species evolve different traits to adapt to their environments.

**Final Answer**: The bones of the forelimbs of the whale, bat, cheetah, and man are similar in structure because they are homologous organs that share a common evolutionary origin, despite having different functions.

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