Hint: Xylem vessels are long tubes that assist in water transport and provide mechanical assistance. By end-to-end union, each xylem vessel is formed by a large number of short, broad, lignified dead cells. The nucleus and cytoplasm are also absent in these cells.
To live, all plants need water. Water found in the soil is taken up by plants. Using xylem vessels, absorbed water is transferred to all parts of plants (stems, leaves, flowers and fruits). Xylem is a complex tissue which consists of xylem vessels and tracheids called dead cells.
Xylem is the vascular plant's specialised tissue that delivers water and nutrients to stems and leaves from the plant-soil interface, and provides mechanical support and storage. One of the major differentiating features of vascular plants is the water-conducting function of xylem.
Water is the primary solvent for plant nutrition and metabolism and is important for the transport of minerals, hormones and other signalling molecules, as well as for photosynthesis and turgor. The water-conducting xylem cells have a hydrophobic inner surface that facilitates both the transport of water and mechanical power.
The xylem cells also sustain the weight of the plant's water borne upwards and the weight of the plant itself. For many trees, xylem is wood, which since ancient times has been a vital raw material for human societies, providing building material, fuel and fibre. The genetic engineering modification of xylem may lead to better sources of energy, improved raw materials and wood products.
Hence, the correct answer is option (C)
Note: Xylem is wood, one of the most available and expensive sustainable raw materials in the world. Its biological, physical and chemical properties and the resulting properties of wood are determined by the morphology, frequency and distribution of types of xylem cells.
Via its carbon storage ability and its resistance to decay while alive or dead, and in different sediments, the chemical and physical properties of wood decide its role in the carbon cycle.