Which logical fallacy is used in the text?
The thing that makes Jeffrey stand out as a remarkable cellist is that he's a marvelous musician who plays the cello splendidly.

 - false dichotomy: an argument that presents only two choices when more options exist
 - ad hominem: an attack against the person making the argument, rather than the argument itself
 - circular reasoning: an argument that supports a claim with the claim itself
The text argues that Jeffrey is a remarkable cellist because he plays the cello well. However, the "evidence" is just a restatement of the claim itself. This illustrates a type of logical fallacy known as circular reasoning.