The correct option is B Salvia
Pollination mechanism in Salvia is a unique lever type. The flowers in this genus are arranged in thyrsus inflorescence and they are attractive and well adapted for cross-pollination through the agency of insects. In this lever mechanism of pollination, the Corolla has a spreading upper lip, which acts as a landing place for the insect. When the insects land on the lower lip of the corolla and in its endeavour to obtain nectar that is secreted by the hypogynous disc, pushes the sterile lobes of the stamen inwards. Due to this the upper half of the connective with the fertile lobes act as a lever. Then the anther lobe comes down and shed the pollen on the back of the insect.