Kohlberg and His Colleagues Eventually Dropped Stage Six from His

Kohlberg and his colleagues eventually dropped stage six from his theory of moral reasoning because:

A) longitudinal research showed that none of the participants showed stage six moral reasoning, and clear-cut expressions of "universal moral principles" are very rare.
B) other researchers, such as Carol Gilligan, argued that stage six was more typical of male moral reasoning and did not reflect how females reasoned.
C) the longitudinal research needed to support stage six moral reasoning in Kohlberg's theory was never carried out.
D) other researchers, such as Carol Gilligan, argued that stage six was more typical of female moral reasoning and did not reflect how males reasoned.