Final answer:
JC's belief that knocking out Gunther is extremely challenging reflects the 'strength' dimension of task-specific self-efficacy, where he acknowledges the difficulty but maintains a certain level of confidence in his ability to achieve the task.
Step-by-step explanation:
Self-efficacy is the belief in one's ability to succeed in specific situations or accomplish a task. The dimension of task-specific self-efficacy that JC's belief reflects, when he considers knocking out Gunther as extremely challenging, is strength. This dimension pertains to the conviction that one has in their capability to perform a task successfully, despite perceiving it as difficult. In the context of the question given, JC's belief in how challenging it will be to knock out Gunther is a reflection of the strength of his self-efficacy regarding this specific boxing task.
To answer the reference question, the level of confidence in one's own abilities is known as self-efficacy (option a).