Which of these food preservation methods kills microorganisms present in a food product, rather than slowing down the growth of microorganisms in it?

Options

A. Canning
B. Freezing
C. Adding oil or vinegar
D. Heating at high temperatures

Answer

To determine which food preservation method kills microorganisms present in a food product rather than just slowing down their growth, let's analyze the options one by one.

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for a method that kills microorganisms rather than merely inhibiting their growth.

2. **Evaluate the Options**:
- **a. Canning**: This method involves sealing food in containers and heating them to kill microorganisms. It is effective in killing microbes, so this option could be correct.
- **b. Freezing**: Freezing slows down the growth of microorganisms but does not kill them. Therefore, this option is not correct.
- **c. Adding oil or vinegar**: These substances can create an environment that inhibits microbial growth but do not kill microorganisms outright. Thus, this option is also not correct.
- **d. Heating at high temperatures**: This method involves applying heat to food, which kills microorganisms effectively. This is a common method used in pasteurization and cooking.

3. **Identify the Correct Answer**:
- After evaluating all the options, it is clear that **d. Heating at high temperatures** is the method that kills microorganisms present in food products.

### Final Answer:
The food preservation method that kills microorganisms present in a food product is **d. Heating at high temperatures**.

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