Boys with conduct disorder are more likely than girls with conduct disorder to engage in which of the following?

Researchers have used Carolyn Rovee-Collier's conjugate reinforcement technique to assess memory during infancy. According to this research,

a. infants show no measurable signs of memory until they are at least 4 months of age. b. if you change the environmental context in which the mobile is presented, infants show much lower retention. c. context apparently does not influence infants' memory. d. unlike adults, infants show no evidence of the spacing effect.

The _____________ is the foundation for present biochemical explanations of schizophrenia.

a.) Polygenic theory b.) Diathesis-stress theory c.) Family pedigree theory d.) Dopamine hypothesis