Final answer:
Hornworts are nonvascular plants and do not have vascular tissue, unlike other options such as carrots, rose bushes, and trees which are all vascular plants.
Step-by-step explanation:
Vascular plants are characterized by their possession of vascular tissue, which includes xylem and phloem for the transportation of water, nutrients, and food within the plant. This group includes a wide range of plants, from carrots to rose bushes and trees, all of which have complex structures like roots, stems, and leaves. On the contrary, nonvascular plants, lack these structures and instead have simpler body plans that facilitate the absorption of water and nutrients directly through their exposed surfaces.
These nonvascular plants, referred to as bryophytes, include mosses, liverworts, and hornworts. Therefore, among the options provided in the question, the organisms that do NOT include vascular plants are hornworts.