Thomsen friedensreich phenomenon is -

Ans. is 'b' i.e., Red cell agglutination by all blood group sera Thomsen-Freidenreich Phenomenono Red cell suspensions contaminated with certain bacteria, e.g. pseudomonas aeruginosa, become aggluiinable by alt blood group sera and even by normal human sera,o This is known as Thomsen Friedenreich phenomenon and is due to unmasking of a hidden antigen normally present on all human erythryocytes, i.e. T-antigen.o Anti-T agglutinins are normally present in human sera.o Such panagglutinability of red cells has occasionally been observed in persons suffering from systemic bacterial infections.