The first reactor mishap occurred in

Options

A. windscale
B. church rock
C. three-mile island
D. kyshym.

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks about the first reactor mishap in history. It is important to differentiate between the first mishap and the worst mishap, as they are not the same.

2. **Identifying the Options**: The options provided are:
- 1. Wind Scale
- 2. Church Rock
- 3. Three Mile Island
- 4. Krishan

3. **Clarifying the Worst Nuclear Mishap**: While the Chernobyl disaster is often referred to as the worst nuclear mishap, it is not the first. The Chernobyl disaster occurred on April 26, 1986.

4. **Finding the First Reactor Mishap**: The first reactor mishap occurred at the Wind Scale facility in England. This incident is known as the Wind Scale fire accident.

5. **Date of the Incident**: The Wind Scale accident took place on October 10, 1957. During this incident, a graphite reactor lost its coolant, leading to overheating of adjacent uranium cartridges and causing a significant fire.

6. **Duration of the Incident**: The fire took approximately six hours to control, and it resulted in the leakage of radioactive materials.

7. **Conclusion**: Based on the information, the correct answer to the question "The first reactor mishap occurred in" is **Wind Scale**.

**Final Answer**: Wind Scale

---