Final answer:
Brenda Lee set a record as the oldest chart-topper on the Billboard Hot 100 thanks to the resurgence in popularity of her song "Rockin' Around the Christmas Tree" especially during the holiday season through digital downloads and streaming.
Step-by-step explanation:
Brenda Lee became the oldest chart-topper in Billboard Hot 100 history thanks to the enduring popularity and streaming success of her classic Christmas song "Rockin' Around the Christmas Tree". Released in 1958, the song failed to make an impact initially but gradually became a staple of holiday music.
With the advent of streaming and digital downloads, it has surged in popularity during the Christmas season each year. This seasonal resurgence in 2023 allowed Brenda Lee, at the age of 78, to top the Billboard Hot 100 chart, setting the record for the oldest artist to achieve such a feat