Which of the following best describes the role of a coroner?

The role of a coroner is best described as investigating deaths and deciding on autopsy necessity. This responsibility entails examining the circumstances surrounding a death to determine whether further investigation or an autopsy is warranted. A coroner is typically charged with understanding the details of a death scene, collecting pertinent evidence, and evaluating medical histories to reach conclusions about the cause and manner of death.

In many jurisdictions, not every death requires an autopsy, and the coroner's judgment is crucial in deciding when it is necessary. This role is essential for resolving legal questions regarding unnatural or suspicious deaths and ensuring that the proper protocols are followed for cases that may require forensic examination.

The other roles mentioned, such as determining the cause of death in all cases or conducting all autopsies, do not accurately reflect the broader responsibilities that a coroner holds. Similarly, while a coroner may be involved in suspicious death cases, they do not typically handle prosecution; that responsibility usually falls to law enforcement and the legal system. Thus, the selected answer captures the essence of what a coroner does within the framework of medicolegal death investigation.