The correct answer is A. Drop panel.
A drop panel is a thickened part of a flat slab over its supporting column. It is used to reduce the bending stresses in the slab and to distribute the load more evenly over the column. Drop panels are typically rectangular in shape and are located at the corners of the column.
A capital is a decorative molding or ornament that is placed on top of a column. It is used to provide a transition between the column and the roof or ceiling. Capitals are typically made of stone, marble, or wood.
A column head is the upper part of a column that supports the roof or ceiling. It is typically made of stone, marble, or wood.
None of these is the correct answer.