A: Catholic Church did not execute scientists. I am not sure where this information was obtained from but to my knowledge it's not true. There have been times where there has been conflict between the Church and some scientists (like Galilee Galileo) but they were not executed. For example Galilee was sentenced with house imprisonment. And in his case the problem was not about science but rather Galilee interfering in to the matters of faith (i.e. how to interpret the Bible). As a further note it should be noted that Galilee was wrong in his scientific theory of Sun being the center of the universe.