What is one evolutionary advantage pteridophytes have over bryophytes?

answer; ///i believe the correct answer is (aids) acquired immune deficiency syndrome;

thrombocytopenia, which is a deficiency in blood platelets, can cause bleeding and bruising in the dermis similar to senile purpura. other possible causes include: exposure to ultraviolet rays and aging skin are common causes of senile purpura. senile purpura may also be a sign of collagen loss in the skin and bones.