Answer:
D. dewpoint
Explanation:
The dewpoint is defined as the temperature to which air (or gas) must be cooled for water condensation to begin, that is, for air to be saturated with water vapor. At dewpoint temperature the amount of water vapor present in the air is maximum.
Air-holding capacity is strongly temperature dependent: hot air can hold more water. Dewpoint temperature can be calculated from relative humidity and air temperature.
A practical example of dewpoint is a glass of cold beer served on a hot day. If the beer's temperature is less than or equal to the ambient dew point temperature, the thin layer of air around the glass cools and releases water on the surface, forming drops.
