(A) barack OBama
(B) Baerack obame
(C) ** Barack Obama
(D) Barack’s Obama’s
EXPLANATIONS BELOW
Concept note-1: -Barack Hussein Obama II (/bəˈrɑːk huːˈseɪn oʊˈbɑːmə/ ( listen) bə-RAHK hoo-SAYN oh-BAH-mə; born August 4, 1961) is an American retired politician who served as the 44th president of the United States from 2009 to 2017.
Concept note-2: -Obama is a surname. It most commonly refers to Barack Obama (born 1961), the 44th President of the United States.
Concept note-3: -Nonetheless, later “The Honorable” became the standard title of the President in formal address, and “His/Her Excellency” became the title of the President when addressed formally internationally.