Mammals giving rise to immature young ones and nursing them in a pouch are

Options

A. Monotremes
B. Marsupials
C. Primates
D. Carnivores

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about a specific group of mammals that give birth to immature young ones and nurse them in a pouch.

2. **Analyzing the Options**:
- **Option A: Monotremes**: These are egg-laying mammals. They do not give birth to live young, so this option is incorrect.
- **Option B: Marsupials**: Marsupials are characterized by giving birth to immature young ones that continue to develop in a pouch. This option fits the description given in the question.
- **Option C: Primates**: Primates can be either oviparous (egg-laying) or viviparous (giving birth to live young). They do not have a pouch for nursing, making this option incorrect.
- **Option D: Carnivores**: Carnivores are a dietary classification and can include both oviparous and viviparous species. This option does not specifically relate to the question about pouch nursing.

3. **Identifying the Correct Answer**: Based on the analysis, the correct answer is **Option B: Marsupials**.

4. **Conclusion**: Marsupials are the mammals that give rise to immature young ones and nurse them in a pouch.

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