Answer:
Courtney cannot perform operations.
Explanation:
According to Piaget's stages of cognitive development, Courtney would be at the pre-operational stage. When children are at this stage, their thinking is still egocentric, meaning they have difficulty to understand and accept the perspective of others. However, at this stage children can already establish stable concepts as well as perform mental reasoning. Still, that does not mean they can perform operations - their reasoning is still physical, so mental tasks are not yet available. That explains why Courtney is able to count the apples when she is holding them, but not when she has to think/imagine them.