Step 1: Prosopagnosia is a specific agnosia in which a person cannot recognise familiar faces, even those of close family or their own face, despite intact vision and intelligence.
Step 2: It results from damage to the fusiform face area in the inferior temporal-occipital cortex, typically the right or bilateral fusiform gyrus. So the correct option is difficulty in identifying known faces.
Step 3: The distractors describe other deficits. Impairment of consciousness is a global change in awareness, not a recognition problem. Being unaware of one's own deficit is anosognosia. Inability to identify objects is visual object agnosia, a different category.
Step 4: Keep the terms separate: face blindness equals prosopagnosia, while object blindness equals object agnosia.