Answer:
Correct answer is: It was a connection between Europe and African trade routes.
Step-by-step explanation:
Mecca was the main pilgrimage city for Muslims, so first option is not correct.
Center of Abbasid Empire was in Baghdad, so second option is not correct.
C is not correct as Cordoba is far away from this markets.
D is correct because Cordoba is located in Southern Spain and normally it was connection with Africa.