Aresearcher asks an irb to waive the requirement for parental permission for a study conducted in schools because the nature of the research requires participation of all the children present in classrooms on the day the research will take place. assuming that the basic research design could be approved by the irb and the school, which of the following requirements must be met before an irb could waive parental permission? (a) the research must pose no more than minimal risk.(b) an independent consultant must approve the waiver.(c) parents must be notified that the study is taking place.(d) the students must be offered an optional classroom activity.