There are many ways
the policies and achievements of Muhammad's successors helped the Arab world.
One of the main achievement was to unite the Arab under one flag instead of
various tribes and communities, as the successors of Muhammad used the term
"Khalifa" which was considered a unanimous leader of all the Muslims
thus any territory that came under Islamic rule or any people who accepted
Islam were united behind "Khlifa" instead of various leaders and
tribal heads.<span>
As there was a central system established in that time of
succession, more focus was placed on developmental structures. For example in
the time of Umar, the second successor various facilities were built for the travelers
and those out on the road.
<span>Trade and commerce evolved due to peace and stability
provided by the central government as opposed to earlier times when caravans
were looted in other tribal territories. </span></span>
Explanation:
I believe that it A. if I am wrong I'm sry and please correct me
I am pretty sure the answer that oyu are looking for is D. I hope I am right and that this helps. Good Luck
