The aging population each day .There must be some kind of interesting activity for the old.
A. has grown
B. grew
C. will grow
D. is growing
网友回答
A. has grown
B. grew
C. will grow
(答案→)D. is growing
解析：句意：老龄化人口每天都在增长。必须有某种有趣的老年人的活动。因为是现阶段正在发生的事情，用现在进行时，所以选D。