单项选择题

Questions 18 to 20 are based on the following passage. At the end of the passage, you will be given 15 seconds to answer the questions. Now listen to the passage. Which group of children have a bias when choosing musical instruments

A.Children who have private music tutors.
B.Children who are 8 or older.
C.Children who are between 5 and 7.
D.Children who are well-educated.