Eutherians are characterized by

Options

A. Skin with glands
B. Hairy skin
C. True placentation
D. Locomotary hind-limbs

Answer

**Step-by-Step Solution:**

1. **Understanding Eutherians**: Eutherians are a group of mammals that are characterized by their reproductive system. They belong to the subclass of Mammalia.

2. **Viviparous Nature**: Eutherians are viviparous, meaning they give birth to live young rather than laying eggs. This is a crucial characteristic that distinguishes them from other types of mammals.

3. **Role of the Placenta**: Eutherians possess a true placenta. The placenta is an organ that develops in the uterus during pregnancy. It plays a vital role in nourishing the developing fetus by transferring nutrients and oxygen from the mother while also removing waste products from the fetus.

4. **Gestation Period**: During the gestation period, the placenta facilitates the exchange of materials between the mother and the fetus, ensuring that the young ones develop properly before birth.

5. **Conclusion**: Given these characteristics, the defining feature of eutherians is the presence of a true placenta, which allows for a more complex and efficient form of reproduction compared to other mammals.

**Final Answer**: C. True placentation

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