Correct option is (a) Pyrethroid insecticide
Easiest explanation: Pyrethroid insecticide is a type of insecticide which has naturally occurring pyrethrins and is derived from a flower named Pyrethrum cineraefolium. These are comparatively safer and they donot have anhy side effects due to its origin from flowers. Whereas, Acaricides is used to control the population of mites, Nematicides are generally used to kill and control the population of nematodes in various places like houses, buildings and agricultural lands and to control Fungus growth, fungicide is used to control the growth.