What is a specific, but limited, time (usually early in an organism's life) during which the organism is particularly susceptible to environmental influences relating to some specific facet of development?

When considering internal validity, the _____ is ideal for use in training evaluation.

A) pre/post design with a control group B) pre/post design C) Solomon four-group design D) single-measure design

Why is it that adults in the sandwich generation may feel more stress than adults at other age periods?

a. Because the sandwich generation involves making the difficult decision to stay in one's house, where space is no longer needed, or moving to a smaller home or apartment. b. Because the sandwich generation involves a "squeezing" of one's priorities, where they must choose to give up certain pursuits due to declining physical abilities. c. Because those in the sandwich generation are right in between their period of generativity and their period of stagnation. d. Because those in the sandwich generation have to care for two generations of people—their parents and their children.