Final answer:
If Mary's boss concludes her behavior was due to her department being under-staffed, he would be making an external attribution, which takes situational factors into account, unlike the fundamental attribution error that overemphasizes internal factors. The correct answer is option a.
Step-by-step explanation:
If Mary's boss decides that her behavior was the result of her reacting to her department being under-staffed, he would be making an external attribution. An external attribution assigns the cause of behavior to situational factors, rather than to personal characteristics or qualities. This contrasts with an internal attribution, which would suggest Mary's behavior was due to her inherent personality or disposition. External attributions tend to align with situational explanations of behavior, taking into account the context and environment in which a person operates.
To further understand, consider the fundamental attribution error, a common tendency in social psychology where people overemphasize internal factors when explaining the behaviors of others. If Mary's boss commits this error, he might unjustly attribute the customer complaints solely to Mary's disposition rather than considering external, situational variables, like being under-staffed.
In conclusion, the best-case scenario described for Mary is an example of an external attribution (Option A).