Can you help me finding the differences please?

Can someone read this article and tell me the 1) key ideas and 2) one key quote (copy and paste the link the article is not to long at all)from

How did the people of latin america come to speak the language of spanish

Which of the following discoveries would be most likely to cause a scientific paradigm shift? a. the discovery of more rings around uranus b. the discovery of a new pathogenic virus transmitted by mosquitoes c. the discovery that a dormant volcano is showing signs of activity d. the discovery of a new species of salamander in the amazon rainforest e. the discovery that excess heat is radiating from the center of the earth and causing global climate change