Answer:
difference in performance
Explanation:
Samantha's lower salary as compared to the male person who is at the same hierarchy level is not because that she is female but it is because of the difference in performance.
When she asked her concern the HR, she learnt that:
The Equal Pay Act is labor law which aimed at abolishing the wage disparity that is based on sex. The difference in the wages can be only due to the difference in performance.