Should Transgendered women be allowed to compete against biological female athletes

The controversy with Fallon Fox is that she plays a combat sports. In other words she punches and kicks women in the face. She also said she identifies as Lesbian. Many people are accusing her that she is a straight man who had sex change because she can't beat men in MMA. She is a former US marine during her times as a man.

Many people speculates that her recent loses are intentional so she will be remained to be allowed to fight women. Renee Richards at least competes in a non combat sports and Billy Jean proved a woman can beat a man in Tennis.