The American Olympic and professional boxer Muhammad Ali was regarded as one of the most important and famous sports personalities of the 20th century. What was his birth name?

Correct option is D

The correct answer is (d) Rocky Marciano 
Explanation:
· However, Muhammad Ali's actual birth name was Cassius Marcellus Clay Jr. (option c).
· He changed his name in 1964 after converting to Islam.
Information Booster:
· Olympic Gold: He won the light heavyweight gold medal at the 1960 Summer Olympics.
· Nickname: "The Greatest."
· Famous Quote: "Float like a butterfly, sting like a bee."
Additional Knowledge:
· Walker Smith Jr.: The birth name of legendary boxer Sugar Ray Robinson.
· Edson Arantes do Nascimento: The birth name of the Brazilian football legend Pelé.
· Rocky Marciano: An American professional boxer who held the world heavyweight title from 1952 to 1956.