Final answer:
The correct format for diagnosis code 425.4 on the UB-04 form is 425.4.
Step-by-step explanation:
The correct format on the UB-04 form for diagnosis code 425.4 is b. 425.4.
The UB-04 form is used for submitting medical insurance claims. Diagnosis codes are used to indicate the reason for the medical service.
In this case, the correct format is simply the code itself, without any leading zeros or periods. So, the diagnosis code 425.4 should be written as 425.4 on the UB-04 form.