Question

Spain came to the New World for all the following reasons except: to find a new route to the East to conquer New World riches to prove the earth was flat

Answer 1

C) To prove the earth was flat was NOT a reason Spain came to the New World, so all the answers are correct except that one.
Spain was looking to find a route to reach the East Indies (India and the Indian subcontinent) and to conquer new world riches, such as the Spice Trade in Asia.