Which of the following events contributed to joseph mccarthy’s rise to power during the early 1950s? the house un-american activities committee was formed. alger hiss was prosecuted and convicted as a soviet spy. the senate passed a resolution to censure mccarthy. republicans gained control of both houses of congress.

The correct answer is Alger Hiss was prosecuted and convicted as a Soviet spy. 

McCarthy became an anti-communist superstar in the United States of America after Hiss was arrested and put on trial. He held speeches about Hiss and this propelled him to political stardom where he started chasing communists everywhere, claiming there were even some in the Army.

The best answer is 
"Alger Hiss was prosecuted and convicted as a Soviet spy"

The prosecution and conviction of Alger Hiss contributed to a general anti-communist paranoia in the country, which  McCarthy capitalized on to rise to greater prominence with his "Enemies Within" speech.