The correct option is A Apply gibberellins
Induction of flowering in Chrysanthemum is possible by providing gibberellins. The gibberellin class of plant hormones has been implicated in the control of flowering in several species. In Arabidopsis, severe reduction or endogenous gibberellins delays flowering in long days and prevents flowering in short days. The gibberellin class of plant hormones plays a role in many processes during plant development, including seed germination, cell elongation and flowering.