Which of the following best describes the development of astronomical telescopes over the past 60 years?
A) Over the 60-year period, telescopes have gradually gotten bigger and more powerful.
B) Although there have been advances in cameras and computing power, telescopes themselves have not changed much in the last 60 years.
C) The world's most powerful telescope remained the same for most of this period, but in the past 20 years many new and more powerful telescopes have been built.
D) The only major change in telescope power has occurred because of our ability to launch telescopes into space rather than operating them only from the ground.
Answer: C