【单选题】

It is often observed that the aged spend much time thinking and talking about their past lives, (1) about the future. These reminiscences are not simply random or trivial memories, (2) is their purpose merely to make conversation. The old person’s recollections of the past help to (3) an identity that is becoming increasingly fragile: (4) any role that brings respect or any goal that might provide (5) to the future, the individual mentions their past as a reminder to listeners, that here was a life (6) living. (7) , the memories form part of a continuing life (8) , in which the old person (9) the events and experiences of the years gone by and (10) on the overall meaning of his or her own almost completed life.

As the life cycle (11) to its close, the aged must also learn to accept the reality of their own impending death. (12) this task is made difficult by the fact that death is almost a (13) subject in the United States. The mere discussion of death is often regarded as (14) As adults many of us find the topic frightening and are (15) to think about it—and certainly not to talk about it (16) the presence of someone who is dying.Death has achieved this taboo (17) only in the modern industrial societies. There seems to be an important reason for our reluctance to (18) the idea of death. It is the very fact that death remains (19) our control; it is almost the only one of the natural processes (20) is so.
A．which
B．what
C．as
D．that