The haem protein complexes, which act as oxidizing agents are known as
a)	Haemoglobin	b)	Myoglobin	c)	Chlorophyll	d)	Cytochrome

(d)

Cytochromes are small proteins (intrinsic membrane proteins) that contain a cofactor, haem, which holds an iron atom. The iron carries electrons and cycles between +2 and +3 oxidation states. These form a part of electron transport chain in mitochondria and chloroplast and act as an electron transporter or electron acceptor in respiration and photosynthesis.