Both Activity and Continuity Theory Suggest That Remaining Active and Engaged

Both activity and continuity theory suggest that remaining active and engaged as we age is a good thing,but they differ primarily in what way?

A) the kind of activities that the elderly participate in
B) the willingness of the elderly to maintain the exact same activities as they grow older
C) the extent to which the elderly are isolated as they grow old
D) the extent to which the elderly are able to adapt to new activities