Informal and formal groups composed of individuals of approximately the same age and status are ________ groups

The discovery of both a specific biological cause and an effective cure for general paresis

a. has been followed by many more similar successes. b. has not been followed by similar success stories. c. was never achieved despite decades of scientific study. d. was finally achieved just within the past few years.

At what age does stranger anxiety first appear?

3 months 6 months 12 months 24 months