Answer:
The correct answer is teaching American Indians to accept European values.
Step-by-step explanation:
This is the correct answer because in the 16th Century Catholic church started losing its influence in Europe, due to process of Reformation. That is why they tried to strengthen their influence in the New World. They built many missions with the goal of converting Natives to Christianity and to learn them how to accept European values.
All other options are not correct because they were not the main reason for the building of this missions.