Answer:
Since Maxwell's father comes to live in their home and can count as Maxwell's dependent, Maxwell should:
Submit a new W-4.
Explanation:
The Form W-4 will enable Maxwell's employer, Big City Office Furniture, to determine the appropriate federal income withholding tax to deduct from Maxwell's monthly salaries. This will enable him to pay the appropriate tax and enjoy the allowance that he can claim for a dependent. According to IRS, Maxwell should "submit Form W-4 yearly and when his financial situation changes."