What is the one CPT modifier that is unique to the Pathology/Laboratory section of the CPT manual?

All of the following are functions of saliva with the exception of one. What is the exception?

A) Buffering of acids ? B) Beginning the digestion process ? C) Antibacterial activity ? D) Lowering the pH in the mouth

____________________ refers to disorders of swallowing

Fill in the blank(s) with correct word