the activities might seem childish, actually they require a lot of strength and determination.
A. Since
B. Although
C. Before
D. If
网友回答
A. Since
B. Although
C. Before
D. If
解析：考查状语从句。句意：尽管这些活动好像可能有点孩子气，但实际上他们需要很大的力气和决心。A. Since 由于，自从 B. Although尽管，虽然 C. Before在。。。之前 D. If如果，根据句意所以Ｂ正确。