Rule reminder
Transformations between consecutive structures often require changing: the correlative marker, the conjunction, and the verb form (indicative ↔ infinitive). The meaning must be preserved exactly. These transformations are tested in CILS, CELI, and PLIDA B2 exams.
ORIGINAL: 'I dati erano così contraddittori che fu impossibile trarre conclusioni.' Which is the BEST formal/academic transformation?