Question

works of art sharing a regional style share what type of characteristics?
subject matter or physical characteristics unique to a specific region
visual characteristics unique to a specific period in time
subject matter and physical characteristics unique to a specific artist
subject matter and materials common to an expression of emotion

Explanation:

Regional - style artworks are defined by elements specific to a region. This includes subject matter that reflects local themes and physical characteristics like techniques or materials typical of that area.

Answer:

Subject matter or physical characteristics unique to a specific region