In contract law, which of the following situations is likely to be seen as an 'offer' rather than as a mere 'invitation to treat'? Select one: 0 A. Displaying a catalogue containing a description of the book 'Business Law' and the statement 'Special offer!'. B. Displaying a poster advertising the book 'Business Law' for sale at a reduced price. C. Displaying a copy of the book 'Business Law' in the window of a bookshop with a price tag attached to it. D. Sending an email containing the question 'Can I buy your copy of the book 'Business Law' for $50?