The clue on the 2nd last screen is ' it = general statement ' but there is no 'it' in the sentence being translated,  just 'I find that topic really interesting.'  

The clue is misleading given the answers suggested, not unexpectedly, use ' ce sujet ' or ' ce thème ' . 

On the following screen "I am going to buy it straight away. " In this case 'it' refers to a specific novel, so 'general statement' is not correct either.

I don't think the clue is helpful or necessary on either screen.