<br/>DMK president and Tamil Nadu Chief Minister M Karunanidhi today congratulated UPA Chairperson Sonia Gandhi on being appointed as the head of the National Advisory Council (NAC). <br/><br/>Karunanidhi, whose party is a key ally of the UPA, said in a message to Mrs Gandhi that the poor of the country would benefit from her services. He added that the country, especially the poor and the downtrodden, will stand benefited to a very great extent by her excellent service as Chairperson of the Council. <br/><br/>Mr Karunanidhi said, this appointment would be another feather in her cap and wished her a happy and useful tenure as the Chairperson of NAC. Mrs Gandhi was appointed NAC chief on Monday.