Good answer, Dick W, but may I add:
Any windspeed's SI units are metres per second.... depending on what the question says (exactly), eg "how are microburst speeds quoted in an ATIS" (kt/1000 ft it appears) vs "what is the measurement windspeed in a microburst" (m/s or kt/1000 ft depending which way you look at it), it may or may not be worth appealing the question.
Of course I like to pick holes in any question I can! In particular met ones (having done it at university).