Correct Answer :
D. A III; B IV; C II; D I
A - Xylem vessel: They are a long straight chain made of tough long dead cells known as vessel elements or vessel members. They have a lignified cell wall and a large central cavity. Vessel members are interconnected through perforations in their common walls.
B - Xylem tracheids: Tracheid is an elongated, tapering xylem cell having lignified, and pitted, intact walls which lacks perforations in the cell wall. Tracheids have pits where the cell wall is modified into a thin membrane, across which water flows from tracheid to tracheid
C - Xylem fibres: they have highly thickened walls and obliterated central lumens. They may either be septate or aseptate.
D - Xylem parenchyma: These cells are living and thin walled, and their cell walls are made up of cellulose. They store food materials in the form of starch or fat and other substances like tannins.