Appeal to unqualified authority fallacy is a logical fallacy that deals with arguments presented by someone in authority but is not qualified but still make unsound logic. In other words, we can say appeal to unqualified authority is when a person makes an argument about an issue that is just one-sided and or biased, and that person has o special qualification to make that appeal.
In the given circumstance, Mary believes that Betty's opinion of creationism as false is true. But the main fallacy is that Betty has a Ph.D. in biology but does not have the expertise to comment or make claims on religion or creation. This appeal by Mary is from an unqualified authority, that is Betty in this case.
