Final answer:
The coder should report this case as Option A: Pneumonia, stage 2 sacral decubitus ulcer, dementia.
Step-by-step explanation:
The coder should report this case as Option A: Pneumonia, stage 2 sacral decubitus ulcer, dementia. The patient's admission diagnoses include pneumonia, dementia, and a sacral decubitus ulcer with partial-thickness skin loss of the epidermis. The stage of the sacral decubitus ulcer is specified as stage 2. It's important for the coder to include all relevant diagnoses and their corresponding stages, as this provides a comprehensive picture of the patient's condition.