[A]: Evolution is a theory.
[R]: As it is based on causes and evidences.

Options

A. If both A and R are true and R is the correct explanation of A
B. If both A and R are true but R is not the correct explanation of A
C. If A is true and R is false
D. If both A and R are false

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion and Reason**:
- The assertion states that "evolution is a theory."
- The reason provided is "as it is based on causes and evidences."

2. **Defining Evolution**:
- Evolution is defined as a slow and continuous process where organisms accumulate variations over millions of years, leading to the emergence of new species. This process is gradual and takes a significant amount of time.

3. **Historical Context**:
- The concept of evolution was significantly advanced by Charles Darwin, who is often referred to as the "father of evolution." His work laid the foundation for understanding how species evolve over time.

4. **Nature of Theories in Science**:
- In scientific terms, a theory is an explanation of an aspect of the natural world that is based on a body of evidence. Evolution is considered a theory because it explains the diversity of life based on the evidence gathered over time, even though the process itself cannot be directly observed in its entirety due to the vast timescales involved.

5. **Supporting Evidence for Evolution**:
- There are various types of evidence that support the theory of evolution:
- **Anatomical Evidence**: Similarities and differences in the anatomical structures of different species can indicate common ancestry.
- **Embryological Evidence**: During development, embryos of different species often exhibit similar stages, suggesting a shared evolutionary history.
- **Fossil Records**: Fossils provide direct evidence of past life forms and their changes over time.

6. **Conclusion**:
- Both the assertion and reason are true. The assertion that "evolution is a theory" is valid, and the reason that it is based on causes and evidences supports this assertion. Therefore, the correct conclusion is that both the assertion and reason are true, and the reason provides a correct explanation for the assertion.

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