Corporate lobbyist Niira Radia was again questioned by the CBI on Thursday in connection with the probe into the 2G spectrum allocation scam. She had appeared before the CBI on Tuesday and this is the third time that the agency has questioned her in connection with the scam.Official sources said Radia, who is in the spotlight over her taped conversations with many including Department of Telecom officials and former Minister A Raja, came to the CBI headquarters in Delhi in the morning and was there till the evening. Though officials remained tightlipped about the line of questioning, sources said she was asked about funding of some telecom companies who were alloted the second generation spectrum from October 2007 to January 2008. On Tuesday too, she was asked questioned about the fundings. She was first questioned on December 21 by CBI officials at her farmhouse in Delhi. The CBI sleuths had earlier also carried out searches at Radia's residence and the premises of her firm, Vaishnavi Communications. The Enforcement Directorate has also grilled her on allegations of money laundering. Supreme Court is closely monitoring the multi agency probe in the allocation of 2G spectrum to certain telecom firms. The apex court has asked CBI and ED to submit status reports on their probe to it by February 10, when the 2G spectrum case will come up for hearing.