The miser gazed . . . . . . . . at the pile of gold coins in front of him.

The correct answer is C. avidly.

Avidly means “eagerly and with great interest.” This is the best choice because it describes the miser’s intense desire for the gold coins. The other choices are not as accurate. Earnestly means “sincerely and honestly.” Thoughtfully means “carefully and thoughtfully.” Admiringly means “with respect and admiration.”