Study the given chart showing the evolution of plants. Answer the following questions:

(a) Identify the plant which acts as an immediate ancestor of both ferns and conifers.
(b) Name the nearest ancestors of flowering plants.
(c) Name the most primitive group of plants.
(d) Psilophyton provides common ancestry to which classes?
(e) Name the common ancestor of Psilophyton and seed ferns.
(f) Name the common ancestor of mosses and tracheophytes.