Anastasia Is Building a Sand Castle at the Beach

Anastasia is building a sand castle at the beach.She is frustrated by the fact that the water keeps washing it away.She has rebuilt the castle five times already,each one a little further from the waves.Her brother Christopher walks up,sees the problem,and proceeds to dig a channel for the water that bypasses her latest sand castle completely.Which cognitive block was Anastasia demonstrating?

A) Functional fixedness
B) Convergent thinking
C) Mental set
D) Thin slicing