In Schaie's (2008) Sequential Research, the Finding That, Within a Given

Multiple Choice

In Schaie's (2008) sequential research, the finding that, within a given cohort, some people show longitudinal decline in certain abilities, some people show stability, and yet others show increases in these same abilities speaks to the concept of

A) acquisition of symbolic knowledge.
B) plasticity.
C) interindividual variability.
D) modification of underlying fluid intelligence abilities.