Questions 17 to 20 are based on the following passage. At the end of the passage; you will be given 20 seconds to answer the questions. Now, listen to the passage. What does the professor mean when he says this "So, baby Mary died at birth, and then another baby Mary came along who survived. Both go into the record books"
A．Two people referred to the record book. B．Even names are not as reliable. C．Two copies of the record book were made. D．Two names were recorded in the record book.