Which property of refrigerants affects their suitability for various refrigeration applications?

The suitability of refrigerants for various refrigeration applications is significantly influenced by their flammability and toxicity. When selecting a refrigerant, it is crucial to consider its safety profile in terms of both its potential to ignite and the health risks it poses to humans. For example, refrigerants that are highly flammable can pose serious risks in systems where leaks might occur, while those that are toxic may endanger the health of individuals working with or around the equipment.

In contrast, while cost and availability are practical considerations, they do not directly impact the physical properties and safety characteristics of the refrigerant itself. Similarly, color and texture are not relevant factors in determining a refrigerant's performance or safety. Therefore, the focus on flammability and toxicity makes this option the most pertinent consideration when evaluating the suitability of refrigerants for refrigeration applications.