Mary Agrees with This Logic: If All Violins Are Musical

Mary agrees with this logic: If all violins are musical instruments,and if all musical instruments make sounds,then all violins must make sounds. However,we then present this situation involving the same logical reasoning: If all Cheetos are eggplants,and if all eggplants are oysters,then all Cheetos are oysters. Mary vehemently denies that Cheetos can possibly be oysters. Taking Piaget's perspective of cognitive development,we would conclude that Mary is in the ________ stage.

A) concrete operational
B) formal operational
C) preoperational
D) sensorimotor