I have to say how Danielle Steel's book "Coming Out " developed. How can anyone possibly know this or am i misunderstanding the question? PLEASE HELP !!
You would normally be asked to say how the story in the book develops, which you learn by reading it. This is quite different to explaining how the book developed, which implies knowing the author's original ideas and the research she may have carried out both before and during the writing of it. You cannot be expected to know that.
I agree, heathfield (although under your second interpretation i think the question would be about how the book WAS developed). We'd need to know the precise wording of the question.