Final answer:
Person A is classified as structurally unemployed due to a decline in demand for their specific skills and expertise.
Step-by-step explanation:
Person A, who lost their job due to a long-term decline in the demand for their specific skills and expertise, is classified as structurally unemployed. Structural unemployment occurs when there is a disjuncture between the skills workers have and the skills employers are seeking. In this case, the decline in demand for Person A's skills has made them unemployed.