A small difference between the readings of the wet and dry bulb thermometers is an indication of

TonyStark10

1 month ago

If the air is dry (low humidity) → evaporation is fast → wet bulb temperature is much lower than dry bulb → large difference.
If the air is moist (high humidity) → evaporation is slow → wet bulb and dry bulb readings are close → small difference.

Therefore, the correct answer is D, High relative humidity