I was able to answer it correctly with no knowledge of JS promises at all, although I have used them in other languages. Being told that there's something trick

I was able to answer it correctly with no knowledge of JS promises at all, although I have used them in other languages. Being told that there's something tricky going on was enough for me to be able to guess the difference between #1 and #2, and all I needed to know for #3 vs. #4 was that promises aren't a language extension that can capture expressions as thunks.