Which Physician's Actions Are Legal Everywhere in the United States

Which physician's actions are legal everywhere in the United States?

A) Dr. Popov gives a terminally ill person who says, "I want die," a prescription for a fatal medication.
B) Dr. Katsaros injects a fatal drug into the veins of a terminally ill person who says, "I want to die."
C) Dr. Cramden puts a fatal substance into the IV (intravenous) injection of a seriously ill person who says, "I want to die."
D) Dr. McKinley withdraws the feeding tube from a terminally ill person who says, "I want to die."