Which of the following conveys a sense of fervor or eagerness?

The term that conveys a sense of fervor or eagerness is "avidly." This word describes someone who is enthusiastic or passionate about something, demonstrating a strong interest or eagerness towards an activity or subject. When someone is said to be engaging in an activity avidly, it implies they are doing so with great energy and enthusiasm, reflecting an intense level of desire or commitment.

In contrast, the other terms describe attitudes that lack enthusiasm. "Apathetic" refers to a lack of interest or concern, suggesting a dispassionate approach. "Indifferent" denotes a state of having no particular interest or concern, which directly opposes the eagerness implied by "avidly." "Complacent" describes a self-satisfied feeling that can lead to a lack of engagement or enthusiasm about improvement. Thus, "avidly" stands out as the term that best captures a sense of fervor or eagerness.