Final answer:
In the early 1900s, personnel administration was closely tied to union-management relations, influenced by legislation such as the National Labor Relations Act of 1935 and the Taft-Hartley Act of 1947.
Step-by-step explanation:
In the early 1900s, personnel administration, as it was then called, was closely tied to union-management relations. The industrial era saw significant shifts in how labor was organized and how workers interacted with management. Significant legislative landmarks such as the National Labor Relations Act of 1935 and the Taft-Hartley Act of 1947 played pivotal roles in shaping labor relations and the evolution of personnel administration. Union membership saw a rise with government support during World War II but faced declines post-war due to changing legal landscapes.
Drawing from the history of U.S. unions and legal regulations that affected labor organizations strongly supports the inference that early personnel administration was indeed closely interrelated with union-management relations, making this the correct answer to the question.