$ In Basidiomycetes, there are preset dikaryotic cells called Synkaryons.
! Four exogenous spored are produced in Ascomycetes.

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 regarding Basidiomycetes and Ascomycetes, we will analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that in Basidiomycetes, there are dikaryotic cells called synkaryons.
- In Basidiomycetes, dikaryotic cells do exist, but they are not referred to as synkaryons. Instead, they are simply called dikaryotic cells. The term "synkaryon" typically refers to a cell with fused nuclei, which is not the case here.

2. **Conclusion on the Assertion**:
- Since the assertion incorrectly identifies the term for dikaryotic cells in Basidiomycetes, we can conclude that the assertion is **false**.

3. **Understanding the Reason**:
- The reason states that four exogenous spores are produced in Ascomycetes.
- Ascomycetes, also known as sac fungi, produce spores called ascospores. These ascospores are formed inside a sac-like structure called an ascus, and they are produced through meiosis. The number of ascospores produced can vary, but it is not limited to four; it can be more.

4. **Conclusion on the Reason**:
- Since the reason inaccurately states that only four exogenous spores are produced, we conclude that this statement is also **false**.

5. **Final Conclusion**:
- Both the assertion and the reason are incorrect. Therefore, the correct answer to the question is that both the assertion and the reason are wrong.

### Final Answer:
Both the assertion and the reason are incorrect.