Read the characteristics of vascular bundles in three unidentified plant parts (X, Y, and Z): Part X: Radial arrangement, exarch protoxylem, cambium absent. Part Y: Conjoint arrangement, endarch protoxylem, cambium present. Part Z: Conjoint arrangement, endarch protoxylem, cambium absent. Identify the correct sequence of plant parts corresponding to X, Y, and Z.

Step-by-step solution

Part X has a radial arrangement of vascular bundles (xylem and phloem arranged alternately along different radii) and exarch protoxylem (protoxylem lies towards the periphery). These are characteristic features of roots. The primary bundles in roots also lack cambium. Part Y has conjoint vascular bundles (xylem and phloem situated at the same radius) with endarch protoxylem (protoxylem lies towards the centre). These features indicate a stem. The presence of cambium between xylem and phloem makes it an 'open' vascu