Sentence:  Heterosexuals may also deny that they themselves could ever be heterosexist, stating such claims as, "I'm not homophobic, I have a gay friend." . . . [I]t sends a message to the individual that she cannot confront this person when he or she <WSD>microaggresses</WSD>. 
Meaning of the word marked with <WSD> tags:  To perform one or more acts of microaggression.