Final answer:
The functional and decorative three-dimensional accessories in question are Mirrors and Table Lamps, which both serve practical purposes and enhance the aesthetics of a space.
Step-by-step explanation:
Accessories that are both functional and decorative blend aesthetics with utility, and the answer to the question is A) Mirrors and table lamps. Mirrors serve a practical purpose by allowing us to view ourselves and our surroundings, but they can also be framed and shaped in such ways that they enhance the decor of a space.
Table lamps provide essential lighting, yet their bases and shades come in various designs that contribute to the ambiance and style of a room.
These objects demonstrate the blend of functionality and decorative arts, reflecting the design theory that everyday objects should not only perform their basic function but also add to the aesthetic quality of our environment. Whether it's through interesting shapes, materials, colors, or styles, designers and artists apply the elements and principles of design to create pieces that both serve a purpose and are pleasing to the eye.