Learn French: C'est le texte le moins convaincant qu'ils interprètent pendant cette audition. - It is the least convincing text that they perform during this audition.

It is in the subjunctive! For regular -er verbs like interpréter, the ils form is spelled exactly the same in both moods. The subjunctive is required here because of the superlative phrase le moins convaincant. Using a superlative makes the statement subjective, which triggers the subjunctive in the following clause.

Why do we see le twice in le texte le moins convaincant?

When a superlative adjective comes after the noun, French requires you to repeat the definite article (le, la, or les). You are literally saying 'the text the least convincing'. If the adjective naturally comes before the noun, you only need one article, like in le meilleur texte.

Why does the accent change to è in interprètent when the infinitive is interpréter?

Interpréter is a stem-changing verb. Whenever the verb ending is unpronounced (like the -ent in the ils form), the last é in the stem changes to a grave accent (è) to reflect how it is pronounced. This spelling change happens in both the present indicative and the present subjunctive!

Why do we use qu' here instead of qui?