Http://www.biocab.org/Carbon_Dioxide_CO2.html
The correct answer is "identifies the feelings underlying the acting-out behaviour ".
This statement shows that the adolescent is recognizing the feelings and is ready to talk about them. This willingness to express this indicates the development of insight and the sincere need to investigate the true source of these behaviours.
By stating that he will never behave like that again and that he will conform to society's norms, he is simply using expressions with no meaning to him. If he discusses seducing other adolescents, he is just manifesting the behaviour that led him to the hospital in the first place.
A population is essentially just a collection of all living things in one category. People are one population, insects are another, etc. Communities are "more organized" populations. Soccer players hang out with soccer players, spiders hang out with spiders. We split into "our people" within our population.
I know that may be a little confusing, but if you have anymore questions feel free to ask. I hope I was able to help. Best of luck!