Presence of mammary gland is the unique character of which class?

Answer

**Step-by-Step Solution:**

1. **Understanding Mammary Glands**: Start by defining what mammary glands are. They are also known as milk glands and are responsible for the production of milk in female mammals.

2. **Function of Mammary Glands**: Explain the primary function of mammary glands, which is lactation. This is the process of producing milk to feed newborns, ensuring their nutrition and survival.

3. **Identifying the Class**: Recognize that the presence of mammary glands is a unique characteristic that distinguishes mammals from other classes of animals.

4. **Conclusion**: Conclude that the class in which mammary glands are a unique feature is the class Mammalia (mammals).

**Final Answer**: The presence of mammary glands is a unique character of the class Mammalia (mammals).

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