Final answer:
A speculum is used to dilate a body orifice for examination, whereas an endoscope is a flexible device used for diagnostics, imaging, and performing surgeries internally.
Step-by-step explanation:
The instrument used to dilate a body orifice is a speculum. A speculum is inserted into an orifice such as the vagina or anus to dilate it for examination purposes. On the other hand, an endoscope is used to explore the interior of the body through its natural orifices or minor incisions, transmitting light and returning images to a video screen for medical diagnostics and surgeries like removing polyps or performing biopsies. Unlike the speculum, endoscopes can have attachments for surgical instruments and are flexible to navigate through the body’s internal environment.