Can a straight man become gay

To those who believe that homosexual preference is homosexual orientation, an innate biological predisposition, the answer is a resounding "no." Contrary to this response, the author presents three cases in which the men switch from heterosexual to homosexual relationships (exclusively in two cases) by means of a sexual encounter initiated by.
Is sexual orientation fluid and/or changeable? Or are some gay and lesbian people really closeted bisexuals? A long time ago, Kinsey told us that bisexuality is much more prevalent than we think.