The age of evolution of man is measured by

Options

A. observing by electron microscope
B. chemical reaction
C. C-14 radiocarbon dating
D. ultraviolet radiations

Answer

To determine the age of evolution of man, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks how the age of human evolution is measured. We need to identify the correct method from the given options.

2. **Evaluating the Options**:
- **Option A: Observing by electron microscope**: This method is not applicable for measuring the age of evolution. Microscopes are used for observing structures at a cellular or molecular level, not for dating.
- **Option B: Chemical reaction**: This option is vague and does not specifically relate to dating methods. Chemical reactions do not provide a means to measure evolutionary age.
- **Option C: Ultraviolet radiation**: Similar to the previous options, ultraviolet radiation does not serve as a method for measuring the age of evolution.
- **Option D: Radiocarbon dating**: This is a well-established method for dating organic materials based on the decay of carbon-14. It is the most relevant option for determining the age of human evolution.

3. **Identifying the Correct Method**: Based on the evaluation, the correct answer is **option D: Radiocarbon dating**.

4. **Understanding Radiocarbon Dating**:
- Radiocarbon dating was developed by American chemist Willard F. Libby in 1950, for which he received the Nobel Prize in 1960.
- This method measures the amount of carbon-14, a radioactive isotope, present in organic materials.
- Carbon-14 is absorbed by living organisms and begins to decay into nitrogen-14 after the organism dies.
- The half-life of carbon-14 is approximately 5,730 years, allowing scientists to date materials up to about 35,000 years old.

5. **Conclusion**: The age of evolution of man is effectively measured using radiocarbon dating, making it the correct answer.