As: Gregor mendel is also known as the "father of biology"
R: He gave the law of Epistasis.

Options

A. If both As and R are correct and R is correct explanation of As
B. If both As and R are correct but R is not correct explanation of As
C. If As is correct, R is wrong
D. If both As and R are wrong.

Answer

To solve the question, we need to analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Gregor Mendel is also known as the 'father of biology'."
- This statement is incorrect because Gregor Mendel is actually known as the "father of genetics." The title "father of biology" is more appropriately attributed to Aristotle.

2. **Understanding the Reason**:
- The reason states that "He gave the law of Epistasis."
- This statement is also incorrect. The law of epistasis was not formulated by Gregor Mendel; it was introduced by William Bateson. Mendel is known for his laws of inheritance, which include the law of dominance, law of segregation, and law of independent assortment.

3. **Conclusion**:
- Since both the assertion and the reason are incorrect, the correct option is that both the assertion and the reason are wrong.

### Final Answer:
Both assertion and reason are wrong.

---