"The engineer presents his work."
Translation:Ingenjören presenterar sitt arbete.
I'm not quite sure that it's never possible to interpret 'work' in this English sentence in a way that could correspond to jobb in Swedish, but at least the interpretation that you mention is the most natural one, so I'm removing the translation with 'job' as 'best' translation (but leaving it as accepted), this means it shouldn't show up in the multiple choice question any more.
I'd say in general, yes, his profession, no, the particular time machine, could be.
Han presenterar sitt arbete means he's talking about something he himself is doing. If he were speaking about being an engineer in general (his profession), it should say sitt yrke. But he is speaking about what he himself is doing. The most likely interpretation in my eyes is that he speaks about what he does at work, including the time machine project he's working on right now :)
Hope this helps, I guess this whole thing is a bit moot.