Offer a definition of developmental psychology that encompasses the notions of continuity and change. describe how developmental psychologists typically study development over time.

Developmental psychology studies continuity and change across the life span.
In general, there are two method that researchers could do to obtain this data.
First is to actually conduct it with a same subject over a long period of time.
The second one is by Cross sectioning people with different ages and compared the data from each age group.

Ithink b is the right answer