Which of the following statements regarding relative humidity is/are correct ?
1. It is an index of the amount of water vapour.present in the atmosphere.
2. It measures the readiness with which vapour will condense from the air.
3. The value of the relative humidity varies inversely with temperature and rises during nights.
4. It is the ratio of the mass or weight of water vapour per unit volume of air measured in grams per cubic meter.
Select the correct answer using the code given below:

Options

A. 1 and 4 only
B. 2 and 3 only
C. 4 only
D. 1, 2 and 3

Answer

D