Complete the sentence: Her mother is looking forward to this as it will mean that she can go back she lived in London, (6) _____

The most suitable answer would be 'C. where she worked for the National Gallery, in Trafalgar Square'. The sentence structure implies the need of a place and the only option that makes sense is C, in relation to the context provided. The sentence will be 'Her mother is looking forward to this as it will mean that she can go back where she worked for the National Gallery, in Trafalgar Square'.