Is there sufficient evidence in sources D-J to explain why the troubles broke out in Northern Ireland in 1969?

I have been given the task to see whether these 7 sources can explain to me why the troubles in Northern Ireland broke out. Not only will I be going through source by source, I will also include other sources which I have found from my own research. The seven sources have a vary in content, from a short text too a cartoon too a video clip. The sources are also varied by beliefs; some are written/drawn in the catholic view and others in protestant ECT.
The first source I plan to discuss is Bernadette Devlin’s account as a pupil at a Catholic Grammar school (Dungannon) in the 1960’s. (Shown below)
Source D

Devlin became a well known name concerning Civil rights (leading character) and was also the youngest women to enter the House of Commons (MP). As she had a lot of support. Normally once seeing the word Catholic/Protestant you who consider that piece of evidence as biased. However why would one wish to lie about their school days? This is a question I asked my self, t...