Which of the Following Situations Can Be Characterized as Frotteurism

Which of the following situations can be characterized as frotteurism?

A) Mike rubs his genitals against a woman in front of him in a crowded subway train
B) Howard is sexually aroused by the smell and feel of worn leather boots
C) Clifford has sexual intercourse with more than two people at the same time
D) Jane and her boyfriend frequently incorporate elements of domination and submission into their sexual play