Hypothetical plant hormones are Florigen, Vernalin, Florigen and vernalin, Auxin

In plants five major types of hormones are found. These are auxin, gibberellin, cytokinin, ethylene and abscisic acid. These hormones can work together or independently to influence plant growth. Apart from these hypothetical hormones has been also considered involved in some functions. For example, vernalin is thought to be helpful in the process of vernalization. Florigen is considered flower inducing growth hormone. So, the correct answer is option D.