The correct option is
C A toxin from Plasmodium species
Malaria is a deadly infectious disease caused by the intraerythrocytic protozoan parasite Plasmodium. Malaria infected red blood cells show the presence of malarial pigment called haemozoin. Haemozoin is a biocrystal synthesized by Plasmodium and other blood-feeding parasites to avoid the toxicity of free haeme derived from the digestion of haemoglobin during invasion of the erythrocytes.