Which technique is used to know the age of fossils?

Explanation

### Step-by-Step Solution:

1. **Understanding Fossils**: Fossils are the preserved remains or impressions of organisms that lived in the past. They are typically found in sedimentary rock layers and provide valuable information about the history of life on Earth.

2. **Importance of Dating Fossils**: To study the evolution of species and understand the timeline of life on Earth, it is crucial to determine the age of these fossils.

3. **C14 Dating Technique**: The primary technique used to determine the age of fossils is known as the C14 dating technique, or carbon dating. This method is based on the presence of carbon isotopes in organic materials.

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