Answer to Question 1
D
Answer to Question 2
In a cross-sectional design, people who differ in age are studied at the same point in time. In cross-sectional research, participants at each age level are different people. That is, they come from different cohorts, where a cohort is defined as a group of people of the same age who are exposed to similar cultural environments and historical events as they are growing up. By comparing participants in the different age groups, investigators can often identify age-related changes in whatever aspect of development they happen to be studying.
Microgenetic designs, currently favored by many researchers who study children's cognitive development, are used in an attempt to illuminate the processes that are thought to promote developmental changes. The logic is straightforward: children who are thought to be ready for an important developmental change are exposed repeatedly to experiences that are thought to produce the change, and their behavior is monitored as it is changing.
Shelled invertebrate fossils of the Ordovician period
Fossil from the Carboniferous period
Observed Mother–Child Arguments at Five Time Points Over an Eight-Year Period
Fetal Period
Embryonic Period
Receptive language usually develops before expressive language