The correct option is D Placentation
Floral formula uses symbols, alphabets and numbers to describe a flower. The floral formula gives information about the symmetry of the flower, the sexuality of the flower (unisexual or bisexual), number of sepals and petals and whether they are free or fused, number of stamens (free or fused), number of carpels (free or fused) and the position of ovary.
Placentation, which is the arrangement of ovules in the ovary, is not represented in a floral formula.