Answer:
I think its B: Sliding filament mechanism
Explanation:
Vascular plants<span> have two distinct organ systems: a </span>shoot<span>system and a </span>root<span> system. The </span>shoot<span> system consists of two portions: the vegetative (non-</span>reproductive<span>) parts of the plant, such as the leaves and the stems; and the </span>reproductive<span> parts of the plant, which include flowers and fruits.</span>
