In a standard 12-lead EKG setup, leads are placed on the limbs: the right arm, left arm, right leg, and left leg. With the right arm amputated, the medical team will need to reposition the lead that would normally be placed on the right arm.
In EKG practice, the right arm lead is usually designated with a white color. Therefore, the medical team will need to reposition the white lead.
Answer: white