Answer:
D. Personality tests
Step-by-step explanation:
Based on the information provided within the question in with regards to Plebbons practices the most likely test would be a Personality Test. This is a test that asks the potential employee questions regarding their personality, such as "Do you often spend time exploring new Ideas?" or "Do people trust you easily?" etc. These questions give the potential employer an idea of the kind of person that you are, and in this situation it would give them a hint as to whether or not you are a loyal and hard working person.