The correct answer is "the study of astronomy".
The Rennaissance is a period in European history that marked the transition of the Middle Age to the Modern Age. It occurred from the 14th century until the 17th century. The principal academics and philosophers during this period focused on "breaking away with the past" throughout their work.
During this age, intellectuals such as Nicholas Copernico made important contributions to how humanity conceived the Universe. Copernicus was the first person to introduce a model of the Universe that placed the Sun at the center of it rather than the Earth. This was highly disruptive for the age, as the Catholic Church, which promoted the opposite, was a highly influential power at the time.