Which are three temperature scales?

• A. Celsius, Fahrenheit
• B. Kelvin, Rankine
• C. Fahrenheit, Celsius, Kelvin
• D. Fahrenheit, Celsius, Rankine

Answer: (C)

Temperature scales you commonly encounter include Fahrenheit, Celsius, and Kelvin. Fahrenheit and Celsius are relative scales with water freezing at 32 degrees Fahrenheit and 0 degrees Celsius, and boiling at 212 degrees Fahrenheit and 100 degrees Celsius at standard atmospheric pressure. Kelvin is the absolute scale, starting at 0 K for absolute zero, with temperature increments matching those of Celsius (K = C + 273.15). So the three that are typically taught and used together are Fahrenheit, Celsius, and Kelvin. Rankine is another scale used in some engineering contexts, but it isn’t the standard trio alongside Celsius and Fahrenheit. The other options omit one of these scales or replace Kelvin with Rankine.