Which of the Following Is TRUE About Research by Schaie

Which of the following is TRUE about research by Schaie and Salthouse?

A) Both agree that adulthood is the time when the level of functioning in a number of cognitive domains is maintained or even increases.
B) Salthouse recently has argued that his longitudinal research on aging and cognitive functioning should not be dismissed.
C) Salthouse agrees with Schaie that cognitive functioning involving accumulated knowledge,such as vocabulary and general information,does not show early age-related decline but rather continues to increase at least until 60 years of age.
D) Schaie has argued that reasoning,memory,spatial visualization,and processing speed begin declining in early adulthood and show further decline in the fifties.