Which logical fallacy is used in the text?
Thanks to her enduring popularity with employees, Lucy Shepherd is the best-liked CEO in our company's history.

 - circular reasoning: an argument that supports a claim with the claim itself
 - false dichotomy: an argument that presents only two choices when more options exist
The text argues that Lucy Shepherd is well-liked, because she's popular. However, the "evidence" is just a restatement of the claim itself. This illustrates a type of logical fallacy known as circular reasoning.