This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of lipid, Subject name: Biochemistry
Which of the following phospholipid has antigenic activity? 
Select and explain. 
A. Plasmalogen, B. Cardiolipin, C. Phosphatidylcholine, D. Sphingomyelin
B: Cardiolipin
Answer: B: Cardiolipin 
Explanation: Classification of PhospholipidsGlycerophosphatides: In this glycerol is the alcohol group. Examples: Phosphatidylethanolamine (cephalin), phosphatidylcholine (Lecithin), phospatidylserine, plasmalogens, phosphatidic acid, cardiolipins, and phosphatides.Phosphoinositides: In this group, inositol is the alcohol, e.g. phosphatidylinositol (lipositol).Phosphosphingosides: Alcohol present is sphingosine (also called as sphingol), an unsaturated amino alcohol, e.g. sphingomyelin.CardiolipinA phospholipid found in mitochondria (inner membrane) and bacterial wall. It is formed from phosphatidylglycerol. Chemically, it is diphosphatidyl glycerol. On Hydrolysis: Cardiolipin yields: 4 mols of fatty acids + 2 mols of phosphoric acid + 3 mols of glycerol (Fig. 4.19).This the only phosphoglyceride that possesses antigenic propeies.Ref: M.N. Chatterjea - Textbook of Biochemistry, 8th edition, page no: 55,57