Coleoptera (beetles) belongs to its own distinct endopterygote lineage and is not grouped with the orthopteroid assemblage, and Mecoptera (scorpionflies) is likewise placed in a separate holometabolous lineage, so both can be set aside. Between the remaining two, Plecoptera is often discussed as a hemimetabolous, exopterygote order, but as per this exam's answer key it is Neuroptera that is classified with the orthopteroid-neopteran group referenced here. Hence, Neuroptera.