The correct option is C Actinomorphic, hypogynous with twisted aestivation
In China rose, the flowers are actinomorphic i.e., it can be divided into two equal radial halves in any radial plane passing through the centre; they are hypogynous, i.e., the gynoecium occupies the highest position, while the other parts are situated below it; they have twisted aestivation ie., one margin of petal overlaps that of the next one and so on.