Q.When the cells produced by the vascular cambium (itself formed by dedifferentiation of interfascicular parenchyma) subsequently lose the capacity to divide and mature into secondary xylem and secondary phloem, this final step of maturing into a specific functional cell type is called:

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Cells from the vascular cambium maturing into secondary xylem and phloem is redifferen …

Redifferentiation is the maturation of cells produced by a dedifferentiated meristem (such as the vascular cambium) into a specific functional cell type once again -- here, the vascular cambium's daughter cells maturing into secondary xylem (inward) and secondary phloem (outward). Differentiation describes the original, first-time maturation of a meristematic cell (not one produced by a dedifferentiated tissue); dedifferentiat …

Trace the sequence: interfascicular parenchyma dedifferentiates to form the vascular cambium; the vascular cambium's own daughter ce …

Labelling this step 'differentiation' -- differentiation is reserved for the first-time maturation of a primary meristem's cells, while 'redifferentiation' speci …