A perfume yielding member of family Poaceae is
Cympopogon citratus
Cymbopogon citratus, commonly known as lemongrass oil or oil grass is the species of monocotyledonous flowering plant belonging to family Poaceae. It is a tropical plant from South Asia and introduced into Southeast Asia. It is often sold in stem form. The leaves are fragrant and they are used in cooking, It imparts flavour similar to lemon juice with a mild sweetness and without significant sourness. So, the correct answer is 'Cymbopogon citratus'.