In 1961 Obama was born in Hawaii, US. His father was an African and his mother was a white American. He grew up in Indonesia and Hawaii. When Obama was 10 years old, he was one of the only three black students at his school in Hawaii. He felt very different from most other students. White girls wanted to touch his hair. A white boy even asked him what his father was. "I lied to them that my father was a Kenyan prince. But I kept asking myself who I am," said Obama. However, 37 years later, the boy made history. Obama became the first black president in US history. Obama's unusual background made him wonder who he was. He once turned to alcohol to help forget this question. With the help of his friends, Obama finally turned his life around at college. His hard work made him a star at Harvard. Later, he became the third black senator  in US history. "Obama's success has made Martin Luther King's dream come true. That is: A man should not be judged by the colour of his skin, but by the content of his character," wrote ABC news. Obama became the first black president in US history when he was   _  .
37 38 47 48
Question: In 1961 Obama was born in Hawaii, US. His father was an African and his mother was a white American. He grew up in Indonesia and Hawaii. When Obama was 10 years old, he was one of the only three black students at his school in Hawaii. He felt very different from most other students. White girls wanted to touch his hair. A white boy even asked him what his father was. "I lied to them that my father was a Kenyan prince. But I kept asking myself who I am," said Obama. However, 37 years later, the boy made history. Obama became the first black president in US history. Obama's unusual background made him wonder who he was. He once turned to alcohol to help forget this question. With the help of his friends, Obama finally turned his life around at college. His hard work made him a star at Harvard. Later, he became the third black senator  in US history. "Obama's success has made Martin Luther King's dream come true. That is: A man should not be judged by the colour of his skin, but by the content of his character," wrote ABC news. Obama became the first black president in US history when he was   _  .
A. 37
B. 38
C. 47
D. 48
Answer: