Q31: TTGWD2-Q21:

Telomerase is an enzyme that is produced only in cells that are actively dividing.  For this reason it is generally absent from body tissues in adults.  Bone marrow is an exception to this rule, however, since even in adults, bone marrow cells continually divide to replace old blood cells.  Cancers are another exception, because their cells are rapidly dividing.

The information provided most strongly supports which of the following?

A.      Telomerase is the only enzyme that is present in cancerous cells but absent from cells that are not actively dividing.

B.       In children, the only body tissues from which telomerase is absent are those in which cells are not rapidly dividing.

C.      The presence of telomerase in bone marrow is no indication of bone marrow cancer.

D.      Cancer of the bone marrow develops more rapidly than cancer growing in any other kind of adult tissue.

E.       The level of telomerase production is always higher in cancerous tissue than in noncancerous tissue.

这里除非有一个隐含假设，癌症不能与正常细胞共存，怎么推出

不存在这个隐含假设

因为题目中给出了2个exception,所以当病症出现时,无法确定就一定是cancer

C指出,telomerase出现不能indicate 就是患有cancer,因为bone marrow本身就在

dividing

不懂，能解释一下吗？

对于原文的解释，我也是不懂。。字面不了解