ANS:C - both 'a' & 'b'

The dry bulb temperature of unsaturated air is always higher than both its dew point temperature and wet bulb temperature.

• Dew point temperature: This is the temperature at which the air becomes saturated with water vapor, leading to condensation. It represents the temperature at which the air has reached its maximum humidity given its current pressure and moisture content.
• Wet bulb temperature: This is the lowest temperature that can be reached by the evaporation of water into the air at constant pressure. It's typically lower than the dry bulb temperature because the process of evaporation cools the air.