(a) Preferred evidence of death. The best evidence of a person's death is—

(1) A certified copy of or extract from the public record of death, or verdict of the coroner's jury of the state or community where death occurred; or a certificate or statement of death issued by a local registrar or public health official;

(2) A signed statement of the funeral director, attending physician, or official of an institution where death occurred;

(3) A certified copy of, or extract from, an official report or finding of death made by an agency or department of the United States or of a state; or

(4) If death occurred outside the United States, an official report of death by a United States Consul or other authorized employee of the State Department, or a certified copy of the public record of death in a foreign country.

(b) Other evidence of death. If the preferred evidence of death cannot be obtained, the individual who must furnish evidence of death will be asked to explain the reason therefor and to submit other convincing evidence, such as sworn statements of at least two persons who have personal knowledge of the death. These persons must be able to swear to the date, time, place, and cause of death.