Answer:
C). Logos
Step-by-step explanation:
As we know, 'logos' is characterized as one of the modes of persuasion(quoted by Aristotle) which aims to persuade the audience regarding an argument using the 'logical appeal/reasoning.'
The given statement employs 'logos' as it puts the historical data that however, the speaker has studied in past and got good grades but if he takes this test today, he may face failure signifying that he may not have studied this time or prepared enough for it. It cannot be ethical(character) or emotional(pathos) as the speaker neither persuades the readers on his past character nor employs emotional descriptions to convince them emotionally. Thus, option C is the correct answer.