Which type of plant requires two growing seasons to complete its life cycle?

The biennial plant is characterized by requiring two growing seasons to complete its life cycle. In the first growing season, biennials typically germinate and develop a vegetative structure, such as leaves and roots, but do not flower. During this period, they store energy and nutrients. It is in the second growing season that these plants flower, produce seeds, and then die. This unique life cycle differentiates biennial plants from annual plants, which complete their life cycle in one growing season, and perennial plants, which live for multiple years.

Deciduous plants, on the other hand, are defined by their habit of shedding leaves annually but do not necessarily follow a specific life cycle pattern tied to the length of time they take to complete their life cycle. This further solidifies the reason why the biennial plant is the correct answer in the context of the question.