阅读理解 Robert Todd Duncan was born in 1903 in the southern city of Danville, Kentucky. His mother was his first music teacher. As a young man, he continued his music study in Indianapolis, Indiana.
In 1930, he completed more musical education at Columbia University in New York City. Then he moved to Washington. For fifteen years, he taught music at Howard University in Washington. At that time, not many black musicians were known for writing or performing classical music. Teaching at Howard gave Duncan the chance to share his knowledge of classical European music with a mainly black student population. He taught special ways to present the music. These special ways became known as the Duncan Technique.
Besides teaching, Duncan sang in several operas with performers who were all black. But it seemed that he would always be known mainly as a concert artist. However, his life took a different turn in the middle 1930s. At that time, the famous American music writer George Gershwin was looking for someone to play a leading part in his new work Porgy and Bess. The music critic of The New York Times newspaper suggested Todd Duncan. Duncan had almost decided not to try for the part as he knew it would not be easy to get it. But he changed his mind. He sang a piece from an Italian opera for Gershwin. He had sung only for a few minutes when Gershwin offered him the part. He became famous because of the part in Porgy and Bess.
Todd Duncan gained fame as an opera singer and concert artist. But his greatest love in music was teaching. When he stopped teaching at Howard, he continued giving singing lessons in his Washington home until the week before his death.

【正确答案】 B

【答案解析】根据第二段倒数第三句“Teaching at Howard gave Duncan the chance to share his knowledge of classical European music with a mainly black student population．”可推知，在霍华德大学教音乐期间，Duncan与他的黑人学生分享了自己的欧洲古典音乐知识，使其能学习并了解欧洲古典音乐，因而为其他潜在的黑人古典音乐歌唱家打开了音乐的大门。故选B。