________there are a large number of chemical factories, the air is likely to be polluted.

A．Where

B．That　　　　

C．Though

D．As

下列CT值从大到小次序排列的是()

A.脂肪—凝血—脑灰质—血液—水—空气

B.骨密质—钙化—脑白质—脑灰质—水—脂肪

C.钙化—凝血—脑灰质—血液—水—脂肪

D.钙化—凝血—血液—脂肪—水—空气

E.骨密质—钙化—脑白质—血液—空气—水