What is the rebuttal in an argumentative essay? the reason an opposing argument is weak
the opposing argument to the main viewpoint
the relevant information that supports an argument
the umbrella statement for all parts of an argument

A rebuttal offers a counter-argument, which is itself a form of argument, by answering and questioning each part of an assertion. The introduction should provide a straightforward conclusion point in the case of a rebuttal article, and the body paragraphs should offer proof and interpretation to disprove the opposing argument.

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).