Answer: Option (D) is the correct answer.
Explanation:
Vapor pressure is defined as the pressure exerted by the vapors which are present on the surface of a liquid.
For example, vapor pressure of water at room temperature is 0.0313 atm.
On the other hand, the temperature at which the vapor pressure of a liquid equals atmospheric pressure is known as boiling point.
For example, boiling point of water at room temperature is .
Thus, we can conclude that vapor pressure can be described as the pressure exerted by a gas above the surface of its liquid.