How did the language of quechua spread throughout the andes? a. the roman catholic church used quechua to preach christianity. b. the spanish conquerors adopted quechua. c. the schools and churches taught quechua. d. quechua and spanish are the same language.

We can immediately reject option D - while Spanish is an Indo-European language, Quechua is an indigenous language of the Americas. 

The Spanish conquerors did not care much about the indigenous population - except if they could covert them, which would make them be seen as defenders of the Christian faith and win them favours with the Pope. 

So they would not teach the indigenous population in secular schools, they would however, try to teach them religion. The correct answer is A - The Catholic clergy believed that Christianity would be adopted faster if translated into an indigenous language.

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