Number 1 is the correct answer
It is a multiply question but your didn't include the choice in this question but the answer in this question is only so3 or s03 only. So3 is the only one that must exist as a set of resonance structures. So3 may be refer to a sulfur trioxide wich means a chemical compound of both trioxide and sulfur.
The answer is C. increasing the temperature of the liquid.
Increasing the temperature of the liquid also means that you are providing energy to the liquid, which makes the molecules overcome intermolecular attractive forces, move more constantly, and become gas molecules.
Hope this would help~
Ok what’s the question sir