Question

why were the main exhibit buildings at the chicago worlds fair called the white city?
they were named after daniel h. white, the director of works for the fair.
their plaster facades had been painted white.
the ku klux klan was a major sponsor of the exposition.
president cleveland said the buildings looked like the white house.

Explanation:

The main exhibit buildings at the Chicago World's Fair were called the White City because their plaster facades were painted white, giving the area a uniform and grand white - hued appearance. The other options are incorrect; there is no connection to Daniel H. White in this naming, the Ku Klux Klan was not a sponsor, and there is no record of President Cleveland making such a comparison to the White House.

Answer:

B. Their plaster facades had been painted white.