Below mentioned pairs of structures is considered to be homologous `:`

Options

A. Wings of Grasshopper and forelimbs of flying Squirrel
B. Tentacles of Hydra and arms of Starfish
C. Forelimbs of a Bat and forelegs of a Horse.
D. Wings of bird and wings of Moth.

Answer

To determine which pairs of structures are considered homologous, we need to understand the definition of homologous structures and analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understand Homologous Structures**:
- Homologous structures are organs that have a similar origin and structure but may serve different functions. They indicate divergent evolution, where species have evolved from a common ancestor but adapted to different environments or functions.

2. **Analyze Each Option**:
- **Option A: Wings of Grasshopper and Forelimbs of Flying Squirrel**:
- The wings of a grasshopper and the forelimbs of a flying squirrel come from different evolutionary origins. Therefore, they are not homologous.

- **Option B: Tentacles of Hydra and Arms of Starfish**:
- The tentacles of a hydra and the arms of a starfish serve similar functions (grasping and feeding) but have different origins. Thus, they are analogous structures, not homologous.

- **Option C: Forelimbs of Bat and Forelegs of Horse**:
- The forelimbs of bats and the forelegs of horses have a similar origin (both are derived from the forelimb structure of a common ancestor) but serve different functions (flying vs. running). Therefore, they are homologous structures.

- **Option D: Wings of Bat and Wings of Moth**:
- The wings of bats and moths serve the same function (flying) but have different evolutionary origins. Hence, they are also analogous structures, not homologous.

3. **Conclusion**:
- The only pair that qualifies as homologous structures is **Option C: Forelimbs of Bat and Forelegs of Horse**.

### Final Answer:
The correct option is **C: Forelimbs of Bat and Forelegs of Horse**.

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