Why did European leaders encourage the spread of Christianity during the Age of Discovery?

Responses

European leaders were concerned about saving the souls of heathens around the world.
European leaders were concerned about saving the souls of heathens around the world.

European leaders knew that the spread of Christianity meant the spread of Western culture.
European leaders knew that the spread of Christianity meant the spread of Western culture.

European leaders were concerned that they would not be able to govern anyone that wasn't Christian.
European leaders were concerned that they would not be able to govern anyone that wasn't Christian.

none of the above
none of the above

It is likely a combination of all of the above reasons. European leaders may have been motivated by a combination of religious, cultural, and political factors when they encouraged the spread of Christianity during the Age of Discovery.