Translation:A bird flies high.
Just wrote the same thing on another discussion page - this is really a huge oversight and should have been taken into consideration at the beginning. OR at least (after explaining the sometime vagueness of Korean sentences) tell us which/what they expect in response! Could have constructed sentences that avoid it too but that is more problematic, and would not prepare people for day to day usage of the language. Sorry- am a bit annoyed by now...
I don't blame you for being annoyed, and am in complete agreement. The lack of consistncy is indeed frustrating, sometimes within the same exercise. Even more frustrating is the inadequacy of the reporting mechanism. The suggested English translation is a very poor rendition of the Korean thought. There is nothing in the Korean sentence to suggest any degree of altitude, nor does the translation demonstrate the essence of the compound verb, which means to go up by means of flying.