Do the chapters talk about the "effectiveness" of parliament as a law maker or the effectiveness of the parliamentary system, i.e. the features of parliament and their effectiveness. These are two different things. However you should look at your legal study design and go by that! whatever it says there, do it. Don't learn irrelevant things.
btw when writing a response, you can't rely on one thing only unless the q specifies so. You should know what they are asking and what to write.