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.

What is your opinion on this question?

C is correct.

C correctly links Telomerase, bone marrow and cancer, all of them were mentioned in the original argument.

I feel its style is very similar to OG11-CR6.

C肯定对，大家帮我看看B有什么问题没，题目中说T只存在于actively dividing的细胞中，也就是非actively dividing的细胞中绝对没有，而B中说非rapidly dividing的细胞中绝对没有T，难道rapidly dividing 和actively dividing还有区别吗?