Which of the following statements is true about evaporative cascade coolers?

Evaporative cascade coolers utilize two or more refrigeration systems arranged in series to achieve greater cooling efficiency and lower temperatures. This design allows the first stage to cool the refrigerant to a certain temperature, which is then passed to the next stage for additional cooling. This sequential process enhances the overall cooling capability, making cascade coolers particularly effective for applications that require temperatures beyond the reach of standard single-stage systems.

The other statements about evaporative cascade coolers do not accurately represent their function or typical applications. While it is true that evaporative cooling does introduce some humidity into the air, cascade systems are primarily focused on achieving cooler air through multiple stages of refrigeration rather than specifically increasing humidity levels. They are not generally employed for standard cooling processes as they are designed for specialized applications that need more advanced cooling techniques. Additionally, while these systems can be effective in various climates, they are often unsuitable for ultra-low temperatures as this requires different types of refrigeration technology, such as those designed specifically for cryogenic applications.