Unique about humans is

Options

A. Free hand
B. Tool use
C. Articulated speech
D. Social set up.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks what is unique about humans compared to other animals. We need to evaluate the options provided: free hand, tool use, articulated speech, and social setup.

2. **Analyzing the Options**:
- **Free Hand**: While humans have the ability to use their hands freely, many other animals also possess this ability.
- **Tool Use**: Humans are known for their advanced tool use, but some animals, like primates and birds, also use tools.
- **Social Setup**: Humans have complex social structures, but social behavior is not exclusive to humans; many animals live in social groups.
- **Articulated Speech**: This refers to the ability to convey thoughts through structured spoken language. This is a feature that is distinctly advanced in humans.

3. **Identifying the Unique Feature**: Among the options, articulated speech stands out as it involves a complex coordination of various physical components (mouth, jaw, vocal cords) and cognitive processes (brain function) that allow humans to express thoughts clearly and effectively.

4. **Conclusion**: Based on the analysis, the unique feature of humans is articulated speech. This ability allows for the expression of complex ideas and emotions through language.

5. **Final Answer**: The unique aspect about humans is articulated speech.

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