The Ptolemaic or geocentric model, which had been studied by the Egyptian astronomer Ptolemy, was overturn during the Reinaissance, when the heliocentric model was promoted and started to be generally accepted.
The geocentric model stated that all astronomical objects: the sun, the moon, the stars, and planets all orbited around the Earth. In opposition, the heliocentric model states that the Earth and other bodies are orbiting around the Sun, which is the center of the Solar System.
After questioning the pre-established and generally accepted theory, the development of a mathematical model of the heliocentric system was done in the 16th century, during the Renaissance, by the mathematican, astronomer and also priest Nicolaus Copernicus. It led to the denominated Copernican revolution, which used the scientific method to overturn a previous wrong conception of the universe.
The answer to that question is A
The decolonization during the 20th century was a major turning point in the world from several aspects. One things was that the political map of the world changed significantly, with lot of new countries emerging on the global scene. The imperialist countries did not had the power they had anymore, and a change of power started to occur. The economic power also started to change, with multiple countries that started to emerge as economic giants. The people from the previously colonized countries started to get their rights, and not be second class citizens and work for outsiders.
The massacre at Wounded Knee in 1890 occurred in response to "<span>d. the discovery of gold at Pike’s Peak" since this was the main reason why settlers were there, although this was not exactly a "response". </span>
