Final answer:
The unprecedented success of golden-age musicals was in part due to the popularity of radio broadcasts and economic depression during that era.
Step-by-step explanation:
The unprecedented success of golden-age musicals was in part due to the popularity of radio broadcasts and economic depression during that era. In the 1920s and 1930s, radio programs became a central form of entertainment, reaching four out of five US households by the late 1930s. The economic depression during that time also contributed to the popularity of musicals as a form of escapism for people looking to forget their worries and enjoy lighthearted entertainment.