The correct option is A 2,4-D
Weedicide is a chemical substance used to kill or remove a weed. It is used to build weed-free lawns by gardeners. Several synthetic auxins are extensively applied for the removal of weeds in agriculture. 2,4-D is commonly used as a selective weedicide to remove the unwanted dicot weeds. It is non-toxic to monocot plants and is thus the basis of killing weeds in rice, wheat, and oat fields.