According to Kanter's Research on Women in Organizations During the 1970s

According to Kanter's research on women in organizations during the 1970s, what held women back from entering the top echelons of most organizations?

A) their lack of managerial knowledge
B) policies that discriminated against women as managers
C) their lack of informal networks with men in the organizations
D) their use of informal networks at their organizations for social reasons