The correct option is B Long and hanging stamens
Insect-pollinated flowers are called entomophilous.Ex: Sunflowers, Orchids, etc. They have the following characteristics:
Flowers are large.
Flowers are usually brightly coloured to attract insects.
Flowers emit the scent and produce nectar.
Pollen grains and stigma are sticky in nature.
Long and hanging stamens are special features of wind-pollinated (anemophilous) plants.