<prompt> Phagocytosis of TB bacilli does not occur because of-Wax DMuramyl dipeptideCord factorPeritrichate Cilia  <response>: Ans. is c i.e., Cord factor o Virulent strains of tubercle bacilli form microscopic serpentine cord in which acid fast bacilli are arranged in parallel chains, cord formation is correlated with virulence. A cord factor has been extracted from virulent bacilli with pateroleum ether. It inhibits migration of leukocytes, causes chronic granulomas, and can serve as an immunologic adjuvant. 