Which of the following is true of sexual harassment?​

A) It has to occur between two people of the opposite sex.
B) Harassment doesn't apply to online activities.
C) The victim has to be the person who is being harassed.
D) ​It has to be unwelcome. 

Sexual harassment can only occur if it is unwelcome, meaning that the behavior is unwanted and inappropriate from the perspective of the person who experiences it. Harassment can occur between people of the same or different genders and can occur in various settings, including online interactions. The victim can be the person who is being harassed directly or can be someone who witnesses the offensive behavior.