The correct answer to this open question is the following.
Three ways in that Humanism and secularism challenged core structures in the medieval world were:
1.- Human beings can use reason as a way to make decisions based on their intellect.
2.- Religion should be out of political and economic decisions that affect a society.
3.- People started to challenge explanations that the Catholic church believe were valid about the natural world.
That was the importance of the Renaissance, that people could free themselves of the rigorous teachings of the Catholic church that imposed its beliefs during the dark ages of Medieval times.
That is why important artists questioned those antique ideas about god and creation and expressed a new form of thinking through art. That was the case of Michelangelo Buonarroti, Leonardo Da Vinic, and Rafael.
