Explanation:

- Putrefy means to decay or rot, particularly referring to organic matter as it decomposes.

- Option 1: Destroy - To destroy is to damage something so badly that it no longer exists or cannot be repaired. Destruction is not the opposite of decay.

- Option 2: Combine - To combine is to merge or bring things together, which doesn’t counteract decomposition.

- Option 3: Decompose - Decompose means to break down into simpler substances, very similar to putrefy.

- Option 4: Contaminate - To contaminate means to make something impure, typically by exposure to a harmful substance, which is not the opposite of rot or decay.

- The most appropriate antonym for putrefy is its reversal or prevention, such as preserve or embalm, but none of these options accurately reflect that. Since the reversed process of decay involves living or restoring life, none of the options exactly match.