Question: Clinton Marius, is a South African writer and performer, he made his first professional appearance singing the lead role in which opera in one act by Gian Carlo Menotti with an original English libretto by the composer?
Sentence (from "Amahl and the Night Visitors"): It was commissioned by NBC and first performed by the NBC Opera Theatre on December 24, 1951, in New York City at NBC studio 8H in Rockefeller Center, where it was broadcast live on television from that venue as the debut production of the "Hallmark Hall of Fame".
Relevant evidence: No