The main independent plant body of pteridophytes is sporophyte. It is differentiated into true roots, true stem and true leaves. The primary root is short lived. It is replaced by adventitious roots. The root has a permanent growing apex. The stems are usually herbaceous (except in some woody ferns) and branched monopodially or dichotomously. The leaves may be small microphyllous (e.g., Lycopodium, Equisetum) or large macrophyllous (e.g., Pteridium, Pteris and other ferns). All the vegetative parts possess vascular tissues (i.e., xylem and phloem) organized in definite groups or steles.
Hence the correct option is D.