What does the red cross on christopher columbus ship?

Christopher Columbus sailed on ships and crews belonging to Isabella I, Queen regnant of Castile and León. Isabella & her husband Ferdinand II of Aragon, had just driven the Moers from the Iberian penisula. Being a Christian Kingdom with the support of the Pope, the Spainish ship sail bore the Holy Cross upon their sails. Spain kept the Cross on their sail for the next 300 years. Just as French ships had the Fleur-de-lis on their sails.

less available tax revenue

this basically means that when they get money from taxes wirth having a lower gdp they get less then what others have with a higher gdp

the answer is c. your welcome.