Question: In the psychological treatment of recurrent childhood nightmares: 
 Options:  <1> The parents are trained to extinguish, ignoring them, the manifestations of anxiety of the child who has suffered a nightmare. <2> The main objective is to ensure the physical safety of the child. <3> Exposure techniques and systematic desensitization are considered well-established treatments. <4> The technique of review in imagination is the one that has received the greatest empirical support. <5> There are no studies about the therapeutic efficacy of hypnosis.
4