Human beings are

Options

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

Answer

**Step-by-Step Solution:**

1. **Understanding Locomotion Types**: First, we need to understand the different types of locomotion mentioned: plantigrade, digitigrade, and unguligrade.
- Plantigrade organisms walk with their entire foot (including toes and metatarsals) on the ground.
- Digitigrade organisms walk on their toes, with their metatarsals elevated off the ground.
- Unguligrade organisms walk on their hooves, with their toes and metatarsals elevated.

2. **Identifying Human Locomotion**: Next, we identify which category humans fall into. Humans walk with their entire foot on the ground, which means they utilize their toes and metatarsals while walking.

3. **Conclusion**: Since humans walk with their entire foot on the ground, they are classified as plantigrade.

4. **Final Answer**: Therefore, the correct answer to the question "Human beings are" is **plantigrade**.

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