Which among the following is incorrect about vascular cambium?

• A. It exists as a layer in between primary xylem and primary phloem
• B. Intrafascicular cambium is formed when cambium cells are in between the primary xylem and phloem
• C. Interfascicular cambium cells are medullary cells that adjoin intrafascicular cambium
• D. A cambial ring is formed in an intrafascicular cambium