Final answer:
To convert Celsius to Kelvin, you add 273.15, aligning with the fact that the Kelvin scale is offset by this amount from the Celsius scale.
Step-by-step explanation:
To convert a Celsius temperature to Kelvin, the correct option is D) Add 273.15. This is because the Kelvin and Celsius temperature scales are offset by 273.15 degrees. The Celsius scale starts at -273.15°C, which is absolute zero on the Kelvin scale. Therefore, the equation for converting Celsius to Kelvin is TK = T°C + 273.15. For example, if the temperature is 22.2°C, to find out what it is in Kelvin you would calculate K = 22.2°C + 273.15, which equals 295.4K.