Queen Isabella and King Ferdinand paid for exploration to cross the Atlantic Ocean because they wanted to

A conquer the Caribbean Islands
B a new route to trade with Asian nations
C on existing trade relationships in the Western Hemisphere
D show that they could use Portuguese technologies .

B a new route to trade with Asian nations

Are you sure

Yes, I am sure. Queen Isabella and King Ferdinand funded Christopher Columbus' voyages in search of a new route to Asia, which would open up new trade opportunities and allow Spain to bypass the Portuguese-controlled routes.