He states have powers that are the constitution does not grant to the national government, but does not deny to the states.
a. delegated
b. concurrent
c. denied
d. reserved

I believe it's D. Reserved

Explanation:

The federal government wanted to "reserve" powers to the states so that congress didn't have all of the power to the US.  Thus forth, the answer is D

i beleive its 1)aids

the conditions that made the byzantine empire vulnerable to attacks by the muslin turks were the sack of constantinople by western crusaders, the conquests of the sultanate of rum, presence of rival kingdoms and finally the set up of fiefdoms at the empire which were owned by the ghazis (turkish warriors).