Psychological egoism claims that whatever we do, we do out of self-interest. Give an example of an act you think is not done out of self-interest, and explain how the psychological egoist might try to interpret that act as selfish?

They are right in that we do things that we like or interests us or we wouldn't be doing them at all but going to the Bathroom is something none many like to do but by the way we are built, this is a necessity instead of a want. Now eating is the  same thing with the exception that we eat what we like or interests us unless youre under 18 and still at home.  Selfishness is a matter of personal opinion in that some will think such while others will care less, Many things we do is down because we have to, like done because of laws like schooling, which side of the street we drive on, etc, but again indirectly many things we do do are because of like and interest