The correct sentence is "The trees' trunks are skinny"
First two are grammatically incorrect while the fourth would have you believe that one tree has multiple trunks.
Human sexual activity, human sexual practice or human sexual behaviour is the manner in which humans experience and express their sexuality. People engage in a variety of sexual acts, ranging from activities done alone to acts with another person in varying patterns of frequency, for a wide variety of reasons
A is the answer in order to avoid mistakes
Answer:
By the way he reacted and responded towards Her or other people or simply look at his facial expression