1. muslims consider muhammad to be
divine.
a prophet.
immortal.
an angel.
2. at the beginning of the eighth century, arab armies crossed the strait of gibraltar and occupied southern
italy.
egypt.
spain.
africa.
3. in 1258, the abbasid caliphate at baghdad was brought to an end by
the mongols.
its own greed.
the seljuk turks.
the umayyads.
4. muslim mathematicians adopted a numerical system from
the greeks.
india.
the ancient egyptians.
the romans.

1.  Muslims think of Muhummad to be a prophet.  He is not divine, whatsoever. 
2. The Muslim armies occupied Spain and formed an Islamic caliphate there for a period of time, before being driven out by the Inquisition. 
3. The Abbasid Caliphate ended in 1258 after Mongols led by Hulagu Khan sacked, successfully, the capital of Baghdad.
4. The mathematicians developed the current wide used system called Arabic Numerals, in the stead of Roman Numerals.  It was developed somewhat from India.

It's most likely choice a, it makes the most sense in my opinion.