Answer:
(3) esterification
Step-by-step explanation:
1) Deposition is a process in which a vapor directly condenses into a solid. It is the reverse of sublimation and therefore a process which involves a physical/phase change.
2) Distillation is a process in which a liquid mixture is separated based on the differences in their boiling points. This is a physical separation and not any form of a chemical change.
3) Esterification is an organic reaction in which a carboxylic acid is treated with an alcohol to form an ester.
4) Sublimation is again a physical/phase change process in which a solid gets converted into a gas.