Which of the following best describes why radio telescopes are generally much larger in size than telescopes designed to collect visible light?
A) Getting an image of the same angular resolution requires a much larger telescope for radio waves than for visible light.
B) Radio telescopes are designed to collect sound rather than light.
C) It is because radio telescopes are used in the daytime and visible light telescopes are used at night.
D) Objects that emit radio waves are always much larger than objects that emit visible light, and therefore require larger telescopes.
Answer: A