Which temperature scale is referred to as the absolute Celsius scale?

The correct answer is Kelvin, which is the temperature scale often referred to as the absolute Celsius scale. The Kelvin scale is designed so that absolute zero, the theoretical lowest temperature possible, is defined as 0 K. This scale starts from this absolute zero point and increments by the same degree interval as the Celsius scale, making it direct in thermodynamic applications.

Using the Kelvin scale is particularly important in scientific contexts where temperature needs to be measured relative to absolute zero, such as in thermodynamics and physical chemistry. This is crucial because many laws and equations in physics rely on the concept of absolute temperature.

While Celsius is a widely used temperature scale in day-to-day scenarios, it does not start from absolute zero. Additionally, Fahrenheit and Rankine serve different specific purposes and do not relate directly as absolute temperature scales the way Kelvin does. The Rankine scale is primarily used in thermodynamics in the United States and has its zero point at absolute zero, but it is not as universally recognized as the Kelvin scale for scientific and engineering purposes.