I have just tried the same - after all, it's the obvious word to choose, being so similar to the Dutch "precies". I have reported it.
Edited to add: I have now seen another sentence in this lesson with the word "precies". From memory, it meant "He is precisely (or exactly) as fast as the horse". I tried the word "precisely" there, and it was counted as correct, which makes it even stranger that it should be marked wrong here.