Regarding the New York Longitudinal Study of temperament, which of the following statements is ...

Regarding the New York Longitudinal Study of temperament, which of the following statements is FALSE?
 
  a. Investigators found that about 65 percent of children could be classified into one of the temperament groups. b. The majority of children, 40 percent, were classified as easy children.
  c. The least common classification assigned to children was difficult, with 10 percent of children falling in thiscategory.
 d. The distinct types of temperament observed in infancy predict later differences in adjustment, with easy infants showing better adjustment.
  e. The study demonstrated that basic temperament cannot be changed.