After a dog had been conditioned to salivate at the sight of meat powder, the meat powder was presented to the dog every three minutes and held just out of the dog's reach. Over the course of several trials, the amount of saliva secreted by the dog decreased to zero, indicating that had occurred.

A. negative reinforcement
B. biological preparedness
C. extinction
D. spontaneous recovery

What was piaget's explanation as to why preschool-age children in the preoperational stage make errors on tasks requiring conservation? a) preschool children's tendency toward centration prevents them from focusing on other relevant features of a situation b) preschool children have not yet developed numerical understanding; therefore, different amounts are meaningless c) preschool children's neural-visual network is not fully matured d) preschool children have not lived long enough and accrued enough experience to know the difference between quantities