Fact 1: Fog is formed by water vapor condensing in the air.

Fact 2: Components of water (H2O) 2.

Given the two facts above, answer the question "What kind of vapor condenses to form fog in the air?" with the following options: 
- h2o
 - Oxygen
 - H20
 - Dew
 - NaCl
 - sodium chloride
 - rain
 - mountain ranges


 

 h2o        