The process in which all micro-organisms are killed by heat treatment is known as

Options

A. Pasteurization
B. Immunity
C. Sterilizatin
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the process in which all micro-organisms are killed by heat treatment. This indicates that we are looking for a specific term related to the elimination of microorganisms through the application of heat.

2. **Analyzing the Options**:
- **Option A: Pasteurization**: This is a heat treatment process used primarily to kill pathogens and extend the shelf life of food products, but it does not necessarily kill all microorganisms. Therefore, this option is not correct.
- **Option B: Immunity**: This refers to the body's defense mechanism against pathogens and is not a process involving heat treatment. Hence, this option is also incorrect.
- **Option C: Sterilization**: This term refers to the complete elimination of all microorganisms, including bacteria, viruses, and spores, through various methods, including heat. Heat sterilization specifically uses heat to achieve this. This option is correct.
- **Option D: None of these**: Since we have identified a correct option (Sterilization), this option is incorrect.

3. **Conclusion**: The correct answer to the question is **Sterilization**, specifically referring to heat sterilization, which effectively kills all microorganisms through heat treatment.

**Final Answer**: The process in which all micro-organisms are killed by heat treatment is known as **Sterilization**.

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