Here's a problem to solve: A glass of cold water is set on a desktop. Later that day, beads of water had formed on the outside of the glass. The most likely explanation for the beads of water is that

Among the 4 following options, which is the correct answer?

- A: some water dripped over the side.
 
- B: the water soaked through the glass.
 
- C: water vapor condensed on the sides.
 
- D: someone sprayed the glass with water.
 