Baby elise has developed a sucking scheme. she knows that to get food she must suck on her mother's breast. now, her mother has begun to introduce solid foods with a spoon. elise immediately sucks on the spoon. this is an example of:

Aresearcher is studying women recently admitted to a state prison. all potential subjects must have children under the age of five. research subjects will be given a basket of toys to use at their children’s first visit that the children can then take home. in assessing this proposal, the irb needs to determine that the toys are: age appropriate. not an excessive incentive. educational. of high quality.