问题补充：
you are grown up, you should not rely on your parents.
A. However
B. Now that
C. How often
D. How long
答案：
A. However
(答案→)B. Now that
C. How often
D. How long
解析：However然而，可是；Now that既然；How often多久一次；How long多长。根据句意：既然你长大了，你不应当依靠你的父母。故用Now that
