Flowers of one of the following plants have six stamens in two whorls with outer whorl having two stamens and inner whorl having four stamens. It also has four free petals and two united carpels with ovules on parietal placentation. The plant is
Mustard has six stamens in whorls. Outer whorl has two short stamens on the lateral side and inner whorl has four stamens in anterio-posterior pairs. It has bicarpellary syncarpous superior ovary with ovules on parietal placentation.