(A) 5th
(B) 42nd
(C) 30th
(D) ** 45th
EXPLANATIONS BELOW
Concept note-1: -Donald John Trump (born June 14, 1946) is an American politician, media personality, and businessman who served as the 45th president of the United States from 2017 to 2021. Queens, New York City, U.S.
Concept note-2: -Donald Trump’s tenure as the 45th president of the United States began with his inauguration on January 20, 2017, and ended on January 20, 2021.
Concept note-3: -The youngest to become president by election was John F. Kennedy, who was inaugurated at age 43. The oldest person to assume the presidency was Joe Biden, the nation’s current president, who was inaugurated at age 78.
Concept note-4: -The 46th and current president of the United States is Joseph R. Biden, Jr. He was sworn in on January 20, 2021.