Nam had just booked a ticket for his favourite singer's concert. He realised
Nam had just booked a ticket for his favourite singer's concert. He realised that it had been called off for no obvious reasons.
A. Scarcely had Nam booked a ticket for his favourite singer's concert when he realised that it had been cancelled for no obvious reasons.
B. Scarcely had Nam booked a ticket for his favourite singer's concert when he realised that it had been postponed for no obvious reasons.
C. Scarcely had Nam booked a ticket for his favourite singer's concert when he didn't realise it had been cancelled for no obvious reasons.