Which logical fallacy is used in the text?
Brandon, you drive a beat-up car from the 1980s. For this reason, we can never allow you to be a lifeguard at the community pool.

 - straw man: a misrepresentation of an opponent's position that makes it easier to argue against
 - ad hominem: a personal attack against one's opponent
The text argues that people who drive old cars are likely to be poor lifeguards. This is a personal attack that isn't relevant to someone's qualifications to be a lifeguard. This illustrates a type of logical fallacy known as ad hominem.