The correct option is C Free central
The arrangement of ovules in the ovary of the plant is called placentation. The placenta is a parenchymatous cushion present inside the ovary where ovules are borne. Placentation is of various types, e.g., marginal, axile, parietal, free-central, and basal.
Primrose has free-central placentation where the ovules are borne around a central column, which is not connected with the ovary wall by any septum.