Which of the following changes to Afro-Eurasian intercultural exchanges occurred in the 13th and 14th centuries as a result of Constantinople’s weakening and the Mongols’ consolidating caravan routes?

a) Greek city-states along the Aegean coast experienced a renaissance in art and culture.
b) Arab cities lost their status as the purveyors of art and scholarship.
c) European cities became centers of cultural rebirth and artistic expression.
d) Tartar trade centers experienced a cataclysmic decline that stifled their cultural ingenuity.