Task: Instance Description Understanding (ontology: Sciences/Biology)

Which of the following definitions best describes the instance 'tribadism'?

A. The practice of cunnilingus.
B. A lesbian sexual practice in which a woman rubs her vulva against her partner's body for sexual stimulation, especially for stimulation of the clitoris. This may involve vulva-to-vulva contact or rubbing the vulva against the partner's thigh, stomach, buttocks, arm, or other body part (excluding the mouth).
C. The arousal of a person by wearing clothing deemed culturally appropriate for their gender.
D. An outdated and offensive diagnosis which posited that not all transgender people are "truly" transgender (or transsexual). Sometimes used and shortened to "trutrans" by some transgender people who wish to elevate themselves above other trans people for any of various reasons.

Answer: A lesbian sexual practice in which a woman rubs her vulva against her partner's body for sexual stimulation, especially for stimulation of the clitoris. This may involve vulva-to-vulva contact or rubbing the vulva against the partner's thigh, stomach, buttocks, arm, or other body part (excluding the mouth).