An example of homologous organs is

Options

A. our arm and a dog’s fore-leg.
B. our teeth and an elephant’s tusks.
C. potato and runners of grass.
D. all of the above.

Explanation

### Step-by-Step Solution:

1. **Understanding Homologous Organs**:
- Homologous organs are defined as organs that have a similar basic structural plan but serve different functions in different organisms.

2. **Identifying Examples**:
- A classic example of homologous organs is the forelimbs of various animals.

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