Rule reminder
Final conjunctions (affinché, perché meaning 'so that') and conditional conjunctions (a meno che non, purché, a condizione che, nel caso in cui) always require the subjunctive. 'A meno che' is always followed by 'non' and the subjunctive, even though the meaning is already negative.
I'm explaining this clearly so that everyone understands. Choose the correct form: 'Spiego chiaramente affinché tutti _____.'