Final answer:
The warning should be found on the patient prescription bottle label.
Step-by-step explanation:
The warning "caution federal law prohibits the transfer of this drug to any person other than the patient whom it is prescribed" should be found on the patient prescription bottle label. This warning is a requirement by the FDA to ensure that prescription drugs are used only by the intended patient and not by others. It is important for patient safety and to prevent misuse or abuse of prescription drugs.