I would pick the one that maybe seems the more natural fit for what you do...
or throw a dart.
Thankfully this classification system makes very little impact on any of the results you see. Very few people actually go through the process of searching a video via narrowed search parameters. On top of that YouTube doesn't really take them into consideration for anything other than a narrowed-parameter search. When a viewer searches a topic YouTube takes into consideration their prior viewing habits; do they prefer long videos or short, do they like bright colors or a muted palette, do they prefer a female presenter or male... there is a LOT that goes into the search results provided (Suggested, Home and Browse are similar in this regard). These are the things that are going to be taken into consideration when YouTube is determining whether to surface your video to a viewer... not whether it is categorized as a Lifestyle or Educational video.