Flowers are vascular plants. Vascular plants have
structures
that transport nutrients
and water within a plant.
A. ball-like
B. heart-like
C. box-like
D. tube-like

I think tube like ... is it right

The actual answer is flowers have heart like structures that transport nutrients and water with in the plants.

nanotechnology is a powerful tool in biomaterials research as it creates numerous possibilities for the engineering of functional molecules. nano-bio refers to projected ability to incorporate biomimicry into various materials at nanoscale.