Final answer:
A supporter of civil service reform in the late 19th-century would most likely believe that public service jobs should be awarded based on merit, as reflected in the Pendleton Civil Service Reform Act of 1883 which aimed to dismantle the patronage system.
Step-by-step explanation:
A late 19th-century supporter of civil service reform would most likely agree with statement (b): Public service jobs should be awarded based on candidates' abilities. This assertion aligns with the central theme of the Pendleton Civil Service Reform Act of 1883, which aimed to establish a merit-based system and eliminate the patronage system, also known as the spoils system.
The Pendleton Act created the Civil Service Commission and mandated that federal jobs be awarded through competitive examinations, ensuring a meritocratic approach to hiring. It addressed the negative aspects of political patronage by emphasizing qualifications over party loyalty.