Transportation: train, car, bike, plane, motorcycle
Parts of the body: heart, lungs, brain, spine, ankle
Action words: run, dance, dash, jump, sit
I think that the sentences that portray a common theme of reluctance of soldier in telling their war stories would be letters B, E, and F. Letter B's statement gave it away with the word 'difficult'. Letter E's idea was concretely evident in the phrase 'suddenly they wouldn't talk anymore', and Letter F seems like it talks about why soldier's don't talk much about their experiences.
A is the answer. Hope this HELPS!!