Among the options provided, the situation that is most likely to contain an outlier is the salaries at a Fortune 500 company. Salaries in such companies can vary widely, sometimes featuring extremely high salaries for top executives that can significantly differ from the majority of salaries within the company, leading to outliers.
While the other options could theoretically also contain outliers, they are less likely to have extreme values compared to the salary data from a Fortune 500 company.