*A radio station is offering to solve once and for all a recurring rumor that the biological father of Khloe Kardashian is O.J. Simpson.

RadarOnline.com is reporting that Sirius XM Satellite personality Gregg “Opie” Hughes of The Opie & Anthony Show announced today that he is offering quarter of a million dollars if Khloe, 27, takes a DNA test to prove that the late Robert Kardashian, O.J.’s one-time lawyer, is her father.

If Khloe accepts, the $250,000 will be donated to a charity of her choice.

As Star magazine revealed in an exclusive, two of Robert’s previous wives — both after his marriage to Kris Jenner ended — have come forward claiming the late attorney told them Khloe is not his biological daughter and she is in fact the result of an affair on Kris’ behalf.

“Robert did question the fact that Khloe was his. Any normal man would if they knew their wife had cheated on him,” Robert’s widow, Ellen Kardashian, told Star. “He never would have considered a DNA test. He loved her very much.”

(L-R) Khloe and Kim Kardashian attend a game between the Phoenix Suns and the Dallas Mavericks at American Airlines Center on Jan. 4, 2012 in Dallas