The correct option is C Polygonaceae
Monochlamydeous flowers have a perianth structure. They do not have a specific corolla and calyx. In polygonaceae, the flowers are bisexual, small and actinomorphic with a perianth of three to six sepals. Flowers lack a corolla. The androecium is composed of three to eight stamens that are normally free or united at the base
So, the correct answer is 'Polygonaceae'