Documented microfossils have been found that are as old as

Options

A. 2.5 million years
B. 3.5 billion years
C. 1.5 billion years
D. 2.5 billion years

Answer

To solve the question regarding the age of documented microfossils, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition of Microfossils**:
- Microfossils are tiny fossils that typically range in size from 0.001 mm to 1 mm. They are primarily remnants of microorganisms.

2. **Identify the Field of Study**:
- The study of microfossils falls under the field known as micropaleontology, which focuses on the examination of these small fossils.

3. **Determine the Age of Microfossils**:
- The question asks for the oldest documented microfossils. According to the information provided, the oldest microfossils of bacteria have been found to be as old as 3.5 billion years.

4. **Evaluate the Options**:
- The options given are:
- 2.5 million years
- 3.5 billion years
- 1.5 billion years
- 2.5 billion years
- Based on the information about the age of the oldest microfossils, we can eliminate the other options.

5. **Select the Correct Answer**:
- The correct answer is 3.5 billion years, as this is the age of the oldest documented microfossils found in Quebec, Canada.

### Final Answer:
The documented microfossils have been found that are as old as **3.5 billion years**.

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