What was the new form of singing that arose because of the availability of electric microphones?

The rise of electric microphones in the early 20th century led to the emergence of crooning, which is characterized by a soft, smooth vocal style that lends itself well to intimate performances. Unlike traditional methods that required singers to project their voices to reach audiences in large spaces, the electric microphone allowed for a more personal delivery, enabling artists to sing in a lower volume and with greater emotional nuance.

As a result, crooning became particularly popular in genres such as pop and jazz during the 1920s and 1930s. This style was exemplified by artists like Bing Crosby and Frank Sinatra, who utilized the microphone to enhance their vocal tone and subtleties, marking a significant shift in vocal performances. This development opened new avenues for expression and changed the way audiences experienced music, allowing for a closer connection between singer and listener.

The other choices, while influential in their own rights, do not directly relate to the specific impact of electric microphones on singing style. Scat is a form of vocal improvisation that originated in jazz, doo-wop is a style of vocal harmony group, and belting refers to a technique used primarily for projecting powerful notes, not a style born from microphone technology.