The nurse is assessing the feet of a client with type 1 diabetes mellitus. Which finding requires immediate intervention by the nurse?

A. A hard, painless nodule may indicate a deformity but is not an emergency. B. Erythema and edema at the base of the left great toe could indicate an infection, such as cellulitis, which requires immediate intervention to prevent complications. C. Decreased response to pain discrimination suggests neuropathy, which is concerning but not immediately life-threatening. D. Painful corns and calluses are chronic issues that need management but are not urgent.