The ruminants are included in the order :

Options

A. Sirenia
B. Proboscidea
C. Perissodactyla
D. Artiodactyla

Answer

**Step-by-Step Solution:**

1. **Understanding Ruminants**: Ruminants are herbivorous mammals that have a specialized stomach structure allowing them to ferment plant-based foods. This fermentation process is crucial for their digestion.

2. **Identifying the Characteristics**: Ruminants typically have a unique stomach with multiple compartments, which aids in the breakdown of tough plant materials. They are also characterized by their even-toed hooves.

3. **Classification of Ruminants**: Ruminants belong to a specific order within the class of mammals. The order is defined by the presence of these unique stomach structures and even-toed hooves.

4. **Determining the Order**: The order that includes ruminants is called Artiodactyla. This order encompasses even-toed ungulates, which includes animals like cattle, sheep, and deer.

5. **Exclusion of Other Orders**: Other orders mentioned, such as Sirenia (manatees and dugongs), Proboscidea (elephants), and Perissodactyla (odd-toed ungulates like horses and zebras), do not include ruminants. Thus, they can be ruled out.

6. **Conclusion**: Therefore, the correct order that includes ruminants is Artiodactyla.

**Final Answer**: The ruminants are included in the order Artiodactyla.

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