Final answer:
The prefix 'thanato' is associated with death and is used in contexts dealing with the end of life, such as euthanasia and thanatology, which is the study of death and dying.
Step-by-step explanation:
The prefix thanato refers to death. In the context of euthanasia, thanato relates to the practices and ethical considerations surrounding a "good death". Euthanasia can be categorized as passive or active, depending on how a patient's life is ended. It can also be voluntary, based on the patient's request, or nonvoluntary, when a decision is made on the patient's behalf because they are unable to do so themselves.