Final answer:
The nurse should document the finding of the black scab, which is likely eschar in a pressure ulcer, and continue to monitor the wound. Removing the scab or applying treatments without further instruction could be harmful.
Step-by-step explanation:
When assessing a bed-bound client's right heel with a thick, leathery, black scab, the correct action by the nurse would be option c: Document the finding and continue monitoring. This type of wound description is consistent with eschar, which is often seen in stage III or IV pressure ulcers, where the dead tissue must be naturally sloughed off or debrided by medical professionals if necessary. Removing the scab could lead to bleeding or infection, and application of a dressing or antibiotic ointment may not be appropriate without further assessment and orders from a physician. Therefore, documentation and ongoing monitoring for signs of infection or changes in the condition are crucial.