Explanation:
Elvis Presley is considered the King of Rock and Roll and one of the most popular musicians of the 20th century. He sold about 1 billion records and had 14 number one singles on the Billboard Hot 100 chart.
Justin Bieber is a pop singer who rose to fame in the late 2000s. He has sold over 150 million records and had 5 number one singles on the Billboard Hot 100 chart. While Bieber is a popular musician, he has not achieved the same level of success as Elvis Presley.