Human beings are

Options

A. Plantigrade
B. Digitigrade
C. Unguligrade
D. None of the above

Answer

**Step-by-Step Solution:**

1. **Understanding Locomotion Types**:
- There are different types of locomotion in mammals based on how they place their feet on the ground. The three main types are:
- Plantigrade: Walking on the soles of the feet.
- Digitigrade: Walking on the toes or digits.
- Unguligrade: Walking on hooves.

2. **Identifying Human Locomotion**:
- Human beings walk by placing the entire foot (including the heel) on the ground. This means that they use the complete foot for locomotion.

3. **Classifying Human Locomotion**:
- Since humans use their entire foot for walking, they are classified as plantigrade.

4. **Evaluating Other Options**:
- **Digitigrade**: Animals like dogs and cats walk on their toes. This does not apply to humans.
- **Unguligrade**: Animals like camels and horses walk on hooves. This also does not apply to humans.
- **None of the Above**: This option is incorrect as we have identified the correct classification.

5. **Conclusion**:
- The correct answer to the question "Human beings are" is **plantigrade**.

**Final Answer**: Human beings are plantigrade.

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