Question

an individual who uses a butter knife to unscrew a screw has overcome:
the confirmation bias.
functional fixedness.
displacement.
standardization.

Explanation:

Functional fixedness refers to the cognitive bias that limits a person to using an object only in the way it is traditionally intended. By using a butter knife (typically for spreading butter) to unscrew a screw, the individual has broken this mental constraint and overcome functional fixedness. Confirmation bias is seeking information to support existing beliefs, displacement is a defense mechanism, and standardization refers to uniform processes, none of which apply here.

Answer:

functional fixedness.