Who appeared before the House committee on American activities and refused to answer questions?

Many individuals appeared before the House Un-American Activities Committee (HUAC) and refused to answer questions, notably during the Red Scare of the 1950s. One of the most famous cases was that of screenwriter Dalton Trumbo, who, along with other members of the Hollywood Ten, invoked the First Amendment and refused to testify about their alleged communist affiliations. This refusal led to their imprisonment and blacklisting from Hollywood.