The correct option is B Histamine
Adipose tissues are subcutaneous (below the skin) fats. The cells of adipose tissues are called adipocytes. Blubber is a thick layer of adipose tissue found in aquatic mammals. It provides buoyancy, insulation, reserve source of food and water.
Histamine is a vasodilator (it dilates the blood vessels).
Serotonin is a vasoconstrictor (it constricts blood vessels).
Heparin is an anticoagulant.