Q. What do you mean by Primary Visual and Auditory Cortex?

Primary Visual Cortex - in posterior aspects of occipital lobes.  Receives visual information from optic nerve (cranial nerve II).   The Visual Association Area (also located in occipital lobe) is involved in interpretation of visual information (based on past visual experiences).

Primary Auditory Cortex - superior margins of temporal lobes.  Receives auditory information from cochlear division of vestibulo-cochlear nerve (cranial nerve pair VIII).   The Auditory Association Area (located also in temporal lobe) permits full perception and interpretation of sound stimuli (ex. music, speech, ...)