The correct answer is:
A. the city-states were centers of trade that competed in cultural development.
During the late Middle Ages, the Italian city-states, such as Florence, Venice, and Milan, became vibrant centers of trade and commerce. This economic prosperity allowed them to invest in art, literature, and education, fostering competition not only in trade but also in cultural and intellectual advancements, which were key factors contributing to the emergence of the Renaissance in Italy.