13.Section 4 makes it an offence for a person (A) intentionally to cause another person (B) to engage in sexual activity (as defined in section 78) without that person’s consent, if he does not reasonably believe that B consents. What is said in the note to section 1 about whether a belief in consent is reasonable also applies here. A may cause B to engage in sexual activity with A (for example, a woman who compels a man to penetrate her); on B himself (for example, where one person forces someone else to masturbate himself); or with another person (for example, where one person makes someone else masturbate a third person). Subsection (3) provides that sections 75 and 76 apply to this offence. Sections 75 and 76 deal with evidential and conclusive presumptions about consent.