What do red blood cells, white blood cells, and platelets have in common?
all are part of lymph.
all are produced in the bone marrow.
all are involved in destroying pathogens.
all are self-secreting hormones.

All are produced in the bone marrow.

Explanation:

Edge 2021

c

explanation:

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.