As part of an experimental study on neuropeptides and their effect on emotions, Hilda administers a certain chemical to a group of teenagers, which has been chosen as the sample. The effects of this chemical include a feeling of elation and a need for affiliation. The group of teenagers considered for research exhibits a need to socialize more with the people on campus. Which of the following is the group of teenagers likely to have been given?
-Oxytocin
-Ghrelin
-Lutein
-Melanin