a)The hypnotist would suggest changes in Robert’s feelings, perceptions, thoughts, or behaviors related to smoking.

b) The hypnotist would stimulate Robert’s five senses using monotonous hypnotic induction and force him to quit smoking.

c) The hypnotist would ask Robert to go to sleep until the hypnosis is over.

d) The hypnotist would ask Robert to do something that is against his will to motivate him to stop smoking.

The answer is a: The hypnotist would suggest changes in Robert’s feelings, perceptions, thoughts, or behaviors related to smoking.

"With the assistance of a hypnotist, a subject chooses what they wish to explore and the hypnotist suggests changes in the feelings, perceptions, thoughts, or behaviors related to this subject."

Hope that helps.