> Does the question "what is the book you read most recently?" mean that I read the entirety of the book, or does it mean the book of which I read any part at all most recently?

I read it as either "The book you have finished most recently, assuming you aren't reading anything else,"

or

"The book you are reading now, and you are DEFINITELY going to finish it."

If it's a book that you're reading, and you don't think you're going to finish it, it doesn't count.

My problem is... I routinely read three or four books at once, sometimes of varying degrees of choice- which do I choose then?

-Rifty