Mecca was an important city for arabs on the arabian peninsula before islam because it was one of the options below as your a. a major port cityb. the capital of arabiac. a pilgrimage site
d. a university town

Mecca was an important city for Arabs on the Arabian Peninsula before Islam because it was a pilgrimage site. During the 4th century, pilgrims flocked to the city of Mecca to perform an act of ritual on a small square building called Ka'aba (a cube in Arabic). Pilgrims would walk seven times around the Ka'aba to worship idols that were scattered inside the cube. Inside the cube there is also a sacred and ancient black stone that pilgrims also pay tribute to when they do their rituals in the Ka'aba. 

Aside from this fact, Mecca served also as a trading post for caravans passing through the route from the Indian Ocean to the Mediterranean.