Why is Vasco Da Gama's voyage in 1499 significant in a global context?
a. It supported Columbus' claim that the world was round
b. It demonstrated that there was a faster passage to Asia than the traditional overland routes
c. It showed the south and east Asian empires that Europe was a mighty trading power and foreshadowed Europe's coming dominance
d. It opened the doors to direct maritime trading and helped to establish permanent links between Europe and Asia