Final answer:
When a mistake is observed, it is important to report it to higher authorities.
Step-by-step explanation:
In the medical field, doctors are not infallible and can make mistakes. When a mistake is observed, it is important to take appropriate action to ensure patient safety and quality of care. The correct response to a doctor's mistake would be to B) Report the mistake to higher authorities. This allows for proper investigation, evaluation, and potential improvement of medical practices.