Match the PGR with its effect on plant organs.
| Column I | Column II |
|---|---|
| (a) Auxin | (i) Delays senescence of leaves |
| (b) Gibberellin | (ii) Promotes root growth and root initiation |
| (c) Cytokinin | (iii) Increases internodal elongation |
| (d) Abscisic Acid | (iv) Promotes abscission of older leaves and fruits |