I think false is the answer for this
Yes, but it wasn't common. Priests knew Latin from translating old documents, and most monarchs would have a decent understanding of it. Most people, however, wouldn't have known it.
The United States is stronger than all those countries combine
It would be that "d. They refused to baptize native converts into the Christian faith", since the Spanish viewed this as a way of solidifying their efforts of religious conversion.
Answer:
To protect her commerce and her manifold interests in even the most distant seas