Concerning the treatment of phobias using classical conditioning, it is true that persons fearful of flying will . first need to address their childhood conflicts that are contributing to this phobia in order to eliminate this fear of flyingb. need to avoid flying as a way to reduce this fearc. first need to address the unresolved conflicts in their lives that are contributing to this phobia in order to eliminate the fear of flyingd. need to associate flying with something pleasurable to reduce this fear

d. need to associate flying with something pleasurable to reduce this fear

Explanation:  

Classical conditioning is also known as Pavlovian one(discovered by Russian physiologist Pavlov) and this is a study that is considering learning with the association. In this case, new pleasurable flying will reduce fear because with it's pleasure, the bad memories will be reduced and that will cause a new response in that person, and that would be flying with no fear. It can be also repeated learning until the person gets a new, appropriate response.