Step-by-step explanation:
Give Tom a verbal warning
Tom works in an international firm. Hanks works as a supervisor and Tom works under Hanks.
Hanks often notices that Tom extends his lunch breaks and most of the time leaves early from office to home. Hanks is not very happy from Tom's such behavior and wants to use a progressive disciplinary method to change Tom's behavior.
So next time when Hank observes Tom doing the same thing leaving early from office and taking long lunch breaks, Hanks should personally give Tom a verbal warning and ask him not to behave in this way.
Thus then answer is "Give Tom a verbal warning".