Which of the following examples can be considered as homologous organs or examples of homology ?

Options

A. Brain of vertebrates
B. Heart of vertebrates
C. forelimb of mammals
D. All of the above

Answer

To determine which examples can be considered as homologous organs or examples of homology, we need to understand the concept of homologous organs and how they are formed.

### Step-by-Step Solution:

1. **Understanding Homologous Organs**:
- Homologous organs are those that have a similar structure but may serve different functions. They arise from a common ancestor and evolve due to divergent evolution.

2. **Examples of Homologous Organs**:
- **Brain of Vertebrates**: The brains of different vertebrates, such as mammals, birds, and reptiles, share a common structural origin despite performing different functions in each species.
- **Heart of Vertebrates**: Similarly, the hearts of vertebrates have a common structural design, although they may differ in size and function across different species.
- **Forelimbs of Mammals**: The forelimbs of various mammals (like whales, bats, cheetahs, and humans) exhibit a similar bone structure (humerus, radius, ulna, carpals, metacarpals, and phalanges) but are adapted for different functions (swimming, flying, running, and grasping).

3. **Conclusion**:
- All the examples provided (brain of vertebrates, heart of vertebrates, and forelimbs of mammals) can be classified as homologous organs because they share a common ancestry and structural similarities despite their functional differences.

4. **Final Answer**:
- The correct option is **"All of the above"** (Option 4).