The greatest flaw in Columbus' plan to reach Asia by sailing west that

AHe greatly underestimated the circumference of the earth and did not know about the existence of the continents of North and South America

BHe did not possess the necessary technology to successfully make such a long voyage and return home safely

CHe could get the better-equipped and better-trained Portuguese mariners to sign on to his plan and help him achieve a successful voyage

DGenoa was too far from Portugal and the differences in language and customs was too great for the two peoples to work together