Questions 13 to 15 are based on the passage you have just heard.
1.[单选题]______- A.It develops more easily in centenarians not actively engaged.
- B.It is now the second leading cause of death for centenarians.
- C.It has had no effective cure so far.
- D.It calls for more intensive research.
2.[单选题]______- A.They care more about their physical health
- B.Their quality of life deteriorates rapidly.
- C.Their minds fail before their bodies do.
- D.They cherish their life more than ever.
3.[单选题]______- A.It has decreased.
- B.It has been exaggerated.
- C.It has become better understood.
- D.It has remained basically the same.