William jennings bryan was the mayor of dayton, tennessee believed evolution should be taught in science classes 3) prosecuted john scopes in the dayton, tennessee, evolution case for teaching evolution 4) was a vocal supporter of the ku klux klan advocated prohibition

The correct answer is statement 3.

In the Scopes Trial, John T. Scopes was arrested for teaching the theory of evolution to biology students. This broke a Tennessee state law, forbidding this practice. In this case William Jennings Bryan, who was a former presidential candidate, was the prosecutor. This means he was working against John T. Scopes during the trial. Scopes was defended by a lawyer named Clarence Darrow.