Hi Librarian,
I had a bit of a rummage and there is no shortage of material floating around. In fact, this question is one of the standard GCSE History questions listed in the teachers guidance notes, so it looks like your teacher is following the standard script, and consequently there are specific guides on the web about how to answer it.
However, ignoring that the most mentioned source I identified was Technology, War and Identities (A world Study after 1900) by Aaron Wilkes. But again this looks like a standard history text so you may already be using it.
http://www.amazon.co.uk/KS3-History-.../dp/1850083479