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2 List the Islamic Trade Routes:

(1) Mecca to Constantinople is one such route in spread of Islam.

(2) Mecca to India is second trade route .

(3) Mecca to Alexandria is the third trade route

(4) Mecca to Aden is the fourth trade route.

These 4 trade routes came very handy in spread of Islam.

I think this what what you where looking for... Hope it helps!

i would go with the last one

i would say your answer is a)

sorry if im wrong