The correct answer is D) The desire to find a sea route to Asia before the Portuguese.
Christopher Columbus estimated that he could sucessfully navigate a voyage to Asia. This was significant because a trade route to Asia would allow a country access to rare and precious resources.
After getting support from Spain for this endeavor, Columbus sailed out hoping to reach Asia to establish a consistent trade. This trade would greatly reduce the price of resources that Europeans bought if it happened. However, Columbus stumbled upon the Americas, changing the course of world history forever.