What about it are you struggling with?
The question is about predicting spectra from structures (or if you prefer, predicting structural features from spectra), so look at each compound and ask, how could it fragment?
e.g. A, loss of a methyl group is going to be favourable, so you should get a strong 119 as the base peak, Other thqn that you're looking at smaller fragment ions like 91 and 77.