Using a nonequivalent control group can result in ______ between groups because participants were not randomly assigned.

The adolescent who will probably find puberty most difficult is

Eric, an on-time maturer. Trisha, a late maturer. Hans, an early maturer. Katya, an early maturer.

The limbic system is most closely connected to the

a. hypothalamus b. endocrine system c. frontal lobes d. thalamus