The correct answer is the catholic church was interested in gaining new converts to the religion.
The exploration of the New World by Europeans countries was heavily influenced by religion. A perfect example of this would be Spain.
Spain, a predominantly Catholic country, saw exploration as a new way to increase the amount of Catholics on a global scale. These Spanish conquerors saw the conversion of Indians to Catholicism as a means to save their souls from their "savage" ways. This idea of converting Indians (aka Native Americans) to Catholicism was based on the concept that Europeans were superior to Indians.