Answer right! ON A TIME EXAM

I think it’s c

Explanation:

worldwide, 780 million people do not have access to an improved water source. an estimated 2.5 billion people lack access to improved sanitation (more than 35% of the world's population)

attacks by the seljuk. a devastating blow to the entire byzantine world was dealt by christian crusaders from the west. the venetians were eager to destroy byzantine power and offered the crusaders money, ships, and part of the spoils of war.

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