Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R:Assertion A: Late wood has fewer xylary elements with narrow vessels.Reason R: Cambium is less active in winters.In the light of the above statements, choose the correct answer:

[Image showing the difference between early wood and late wood in an annual ring]Assertion A is correct: Late wood (autumn wood) is produced at the end of the growing season. It has fewer xylem elements and the vessels are much narrower.Reason R is correct: In winter, the environmental conditions are less favourable, and the vascular cambium becomes significantly less active, leading to the production of fewer and smaller cells.Since the reduced activity of the cambium (R) is the direct cause of the structural characteristics of late wood (A), R explains A.