Option (A) is correct because the xylem tissue forms a continuous system of water-conducting channels that reach all parts of the plant. The vessels and tracheids in roots, stems, and leaves are interconnected to transport water from the soil. Additionally, xylem moves minerals dissolved in water from roots to leaves. Options (B) and (C) are incorrect because the transport of food and amino acids occurs through the phloem, not xylem. The phloem transports the products of photosynthesis and amino acids to storage organs and growing parts of the plant. Option (D) is incorrect as the context does not mention oxygen transport as a function of xylem.