A 60-year-old man with a history of diabetes presents to your office with a complaint of thickened and discolored toenails. He tells you that his toenails have had this appearance for over a year, and now he is experiencing discomfort when wearing tight-fitting shoes. Physical exam reveals hyperkeratosis and onycholysis of bilateral great and second toes. Which of the following is the most appropriate next step in management?a. Begin treatment with oral terbinafineb. Check serum aminotransferasesc. Potassium hydroxide examination of toenail scrapingsd. Watchful waiting
