Melanie Is Asked the Question, "What If Humans Never Had

Melanie is asked the question, "What if humans never had hands or feet?" Though she knows most humans do have hands and feet, she says, "Well, I guess we wouldn't have the need for shoes or gloves anymore. Hmmm...I suppose it might be really difficult for humans to keep their balance if they didn't have feet." According to Piaget, in what stage is Melanie?

A) reversibility
B) preoperational
C) formal operations
D) concrete operations