Question

When the top of a glass carbonated water bottle is removed, pressure is released and gas bubbles are observed. Where did this gas come from?
A. It was dissolved in the water.
B. It was clinging to the inside of the bottle.
C. It formed when the water chemically reacted with the air.
D. It formed when the water physically reacted with the glass.

Answer 1

It was dissolved in the water.

When the pressure is reduced, the water can't hold as much gas
in solution, so some of the gas comes out of solution. 

If the pressure is allowed to drop too fast, then the gas comes out
of solution really fast, and some of the solution also jumps out of the
bottle, and you have to wipe it up before you pour any drinks from the bottle.