What is the name given to the principle of biological development that growth proceeds from the middle of the body outward?

According to Freud, the hidden, unconscious desires expressed indirectly in a dream's symbolic content is its __________ content

a. primary b. secondary c. manifest d. latent

What term did Cumming and Henry use to describe the shrinkage of social contacts and social roles in old age?

a. interiority b. introversion c. disengagement d. role decline