Which logical fallacy is used in the text?
Carrie said there's no way Scotland's Loch Ness Monster is real, but she's not even Scottish, so there's no way she could really know.

 - straw man: a misrepresentation of an opponent's position that makes it easier to argue against
 - appeal to nature: the assumption that natural things are always good
 - ad hominem: an attack against the person making the argument, rather than the argument itself
The text argues that Carrie's claim that the Loch Ness Monster isn't real is not valid because she's not Scottish. This is a personal attack on Carrie's background that isn't relevant to whether her claim is valid. This illustrates a type of logical fallacy known as ad hominem.