Rule reminder
Tense sequence in concessive clauses: (1) Main clause PRESENT/FUTURE → concessive uses congiuntivo PRESENTE or PASSATO. (2) Main clause PAST (imperfect, passato remoto) or CONDITIONAL → concessive uses congiuntivo IMPERFETTO (simultaneous) or TRAPASSATO (prior action). Mixing these tenses is one of the most common advanced errors.
Which sentence has a tense SEQUENCE ERROR?