Final answer:
In astronomy, an interferometer is used to improve the angular resolution of radio telescopes by electronically linking multiple telescopes, which significantly increases the resolvable detail.
Step-by-step explanation:
In astronomy, an interferometer can be used to improve the angular resolution of telescopes. Specifically, it is commonly used in radio astronomy to enhance the detail resolvable by linking two or more radio telescopes electronically. The creation of an interferometer array combines the abilities of multiple telescopes to function like a plethora of two-dish interferometers, all observing the same point in space. This method substantially increases the resolution equivalently to what would be achievable with a single, much larger aperture telescope.
Interferometry has also been applied to visible-light and infrared observations, allowing for observatories to begin using multiple telescopes as interferometers. This technique benefits from the interference of multiple waves, providing more detail than possible with a single telescope. The resolution attained is dependent on the separation between the telescopes, which can be extended even further by utilizing precise timing methods and combining data without a physical connection between the dishes. This has enabled far superior resolutions, surpassing those of traditional visible-light telescopes.
To answer the given options in the student's question, b- improve the angular resolution of radio telescopes is the correct function of an interferometer in the context of radio astronomy.