Which of the Following Statements Is True Regarding Sexual Harassment

Which of the following statements is true regarding sexual harassment?

A) If the sexual harassment is perpetrated by a co-worker (rather than a supervisory employee) employers are liable if they knew or should have known of the harassment.
B) The employer cannot be held liable for the supervisory or managerial employees who sexually harass their subordinates.
C) Employers are not responsible for harassment perpetrated by outsiders who deal with the company and harass its employees.
D) The employer cannot be held liable for the supervisory or managerial employees who sexually harass their subordinates if they didn't know of the harassing activity.