Which hormone's reduction in its amount causes a bush to become more bushy (have more lateral growth) after trimming a shrub?

Question

Quizplus · Accepted Answer

Auxin is a plant hormone responsible for regulating plant growth patterns, including apical dominance, which is the phenomenon where the main, central stem of the plant grows more dominantly than the side stems. When the top of a shrub is trimmed, the concentration of auxin decreases, reducing apical dominance and allowing for more lateral (side) growth, making the bush appear bushier.

Which Hormone's Reduction in Its Amount Causes a Bush to Become