Which president supported civil service reform and questioned high protective tariffs?

The correct answer is Chester A. Arthur. He is particularly known for his efforts in civil service reform, notably through the Pendleton Civil Service Reform Act of 1883, which established that positions within the federal government should be awarded on the basis of merit rather than political affiliation. This marked a significant shift towards a more professional and less corrupt governmental system.

Arthur's administration also questioned high protective tariffs, as he recognized the growing discontent among various sectors of society regarding the economic implications of such policies. By advocating for reforms, he aimed to balance the interests of both protectionist voices and those seeking lower tariffs, reflecting the evolving economic landscape of the time.

In contrast, while Rutherford B. Hayes did advocate for some civil service reforms, and James A. Garfield briefly supported reform measures during his short presidency, their overall influence on this issue was not as significant as Arthur's. Grover Cleveland, on the other hand, was more focused on lowering tariffs and had a strong stance against the protective tariff system, but his civil service reform actions came later in his presidency and were not his initial focus.

Thus, Chester A. Arthur stands out as a key figure in both supporting civil service reform and engaging with the contentious issue of protective tariffs during his presidency.