Solution

Angiosperms, also called flowering plants, have seeds that are enclosed within an ovary (usually a fruit), while gymnosperms have no flowers or fruits, and have unenclosed or “naked” seeds on the surface of scales or leaves. A vessel element or vessel member (trachea) is one of the cell types found in xylem, the water conducting tissue of plants. Vessel elements (tracheae) are typically found in flowering plants(angiosperms) but absent from most gymnosperms such as conifers. The main function of the sieve tube is the transport of carbohydrates, primarily sucrose, in the plant (e.g., from the leaves to the fruits and roots). Unlike the water-conducting xylem vessel elements that are dead when mature, sieve elements are living cells. Sieve cells are specialized cells in the phloem tissue of flowering plants or angiosperms. Angiosperms and not gymnosperms are associated with companion cells (closely associated with a sieve element).
So, the correct option is 'all of these'.