Which term can describe doing something with vigor?

The term that describes doing something with vigor is "enthusiastically." When someone approaches a task with enthusiasm, it conveys a sense of energy, eagerness, and passion. This mindset typically results in a more dynamic and committed effort toward completing the activity. Enthusiasm often fuels motivation and the willingness to engage fully, capturing the essence of vigor in action.

In contrast, the other terms present a different tone. Hesitantly implies a lack of confidence or uncertainty, which does not align with a vigorous approach. Reluctantly suggests a forced or unwilling participation, lacking the energy and eagerness that characterize enthusiastic actions. Nervously indicates anxiety or apprehension, which also detracts from the vigor associated with an enthusiastic attitude. Thus, "enthusiastically" is the clear choice for describing a vigorous approach to activities.