At preschool, it is Tyler's fourth birthday. Although Christine is only 3, she insists that she is older than Tyler because she is taller than Tyler. Christine focuses on height as a measure of age. This is an example of

Centration

Explanation:

Centration is one of the actions that stand out within the preoperational stage of Piaget's theory of cognitive development. This stage starts from 2 years and can last up to 7 years. In centration, one tends to highlight only one aspect of a situation and neglect others that may also be very relevant. The child at the center has difficulties thinking and seeing situations from other contexts.

In this case, Christine when seeing that she is taller than Tyler understands that it is an indication that she is older than him. Here Christina is not taking into account other aspects, only her height to determine that she is greater than Tyler.

"choosing is refusing" means individuals face an opportunity cost with each decision they make. economists state that every decision involves trade-offs. opportunity cost is the least desirable alternative given up as a result of a decision.