Which of the following documents may be needed for cremation?

A death certificate is an essential document required for the cremation process. This legal document serves as proof of death and provides necessary information about the deceased, which is crucial for the crematory and for adhering to legal requirements. Additionally, the death certificate helps facilitate the cremation process by ensuring that all procedures comply with state regulations and that the deceased's identity is verified before the cremation occurs.

The other documents mentioned, while potentially relevant in other contexts, are not specifically required for the process of cremation. A will outlines the deceased's wishes regarding their estate and may not address the specifics of the cremation process. A marriage license is related to marital status but does not provide information about the death or authorize cremation. A power of attorney grants someone authority to act on behalf of another person but generally ceases upon death, making it irrelevant to the cremation process itself. Hence, the death certificate stands out as the necessary document in this scenario.