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(i) It is a non-living, elongated cell with tapering ends. its wall is highly thickened with
(ii) Except at certain places circular spots known as
(iii) and (iv) is a cylindrical tube-like structure placed one above the other end to end.
(v) is a non living, thick-walled cell providing mechanical support?
A. (i) Vessel (ii) lignin (iii)stoma(iv) tracheid (v)xylem fiber
B. (i) Tracheid(ii) suberin (iii)pits (iv) vessel (v) parenchyma
C. (i)Vessel (ii) suberin(iii)stoma (iv)tracheid (v) sclereid
D. (i)Tracheid(ii)Lignin (iii)pits (iv) vessel (v) xylem fiber

Answer
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Hint: Xylem is a complex network that is part of the vascular bundle. This is essential for water and solute management and maintenance. The tissues that make up the xylem are tracheids, vessels, xylem fibres, and xylem parenchyma, Of the listed elements, only parenchymal cells are alive, the rest are dead. Sclerenchyma is a simple tissue that is of two types: fibres and sclereids.

Complete answer:
Let’s study each statement one by one.
Tracheids -Tracheids are cells that grow strongly along the long axis of the organ. The cells die due to the lack of protoplasts. The tracheids have cavities of considerable size without content, and the ends are blunt or chiselled. End walls usually do not taper evenly in all planes. Tracheids have a rounded shape or different cross-sections. In fact, from a phylogenetic point of view, it is the most primitive and most basic cell type in the xylem. The trees of old vascular plants consist only of tracheids. It is the only type of element found in fossil seed-plants.
Vessel -This is the starting element for the xylem. The basic structure of vessels is the same as that of tracheids. The lumen of the vessel is wide in comparison to tracheid, and its end wall is perforated (it is porous if there is no transverse barrier between the two vascular elements). Thus, vessels can carry more water than tracheids. Due to the perforated end walls, the container acts as a conduit while the water is conductive. Vessels usually have simple holes in their sides. The type of wall thickening is the same as the type of tracheid.
Among the above options of the first part, only tracheids and vessels are non-living. But among the tracheids and vessels, tracheids have a tapering end. So the answer to this statement is tracheids.
For the second statement, there are three options: suberin and lignin. Lignin is mainly stored in the tracheids, vessels, xylem fibres, and phloem fibres.
Now coming to the third statement it has two options pits and stoma A Pits is a relatively thin section of a cell wall through which adjacent cells can communicate or exchange fluid. Depression is characteristic of cell walls with a secondary layer. Usually, each hole in the next cell has an additional hole. These additional holes are called "pit pairs".
So for the third part the correct option is a pit.
Now in the fourth part, we have two options: tracheids and vessels. We have already discussed tracheids and vessels. We know in tracheids and vessels, the vessel is made up of many cells called vessel members which are cylindrical structures and arranged one above the other So the answer to this part is a vessel.
This part has three options xylem parenchyma xylem fibre and sclereid. We know that xylem parenchyma and sclereids both are living components. So, the answer to this question is xylem fibre.
Xylem Fibers-Xylem fibres provide strength to the tracheid and vessels. These fibres impart strength to the vessels. They are more common on the secondary xylem.
Now let’s summarise the results
-Tracheid
-Lignin
-Pits
-Vessel
-Xylem fibres
So, the correct answer is “Option d”.

Note:
The vascular system occupies a unique place in the plant organism both in terms of its importance and physiological significance. In recent years, a new type of tracheophyte has been introduced, which includes all vascular plants. It contains pterosaur and spermatozoa of the previous classification. Vascular connections form a continuous and interconnected system in various plant organs. The neck and phloem together form the conductive tissue in the plant. They are found in primary and secondary vascular tissues. Their origins vary. The anterior filaments of the apical meristem develop into the primary pharynx and primary phloem.