Bolting/abscission is shown by gibberellins.

Explanation

**Step-by-Step Solution:**

1. **Understanding Bolting:**
- Bolting refers to the rapid elongation of the stem in certain plants, leading to the production of flowers. This process typically occurs before the harvest of crops to ensure that seeds can be produced.

2. **Role of Gibberellins:**
- Gibberellins are a group of plant hormones that play a crucial role in various developmental processes, including bolting. They stimulate stem elongation and promote the transition from vegetative growth to flowering.

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