单项选择题

A.1.8~2Gy/次,总量为50~60Gy
B.2~3Gy/次,总量为50~60Gy
C.1~1.5Gy/次,总量为50~60Gy
D.先1~1.5Gy/次,逐渐加量至1.8~2Gy/次,总量为50~60Gy
E.先1~1.5Gy/次,逐渐加量至1.8~2Gy/次,总量为40Gy