Humans are the only animals that blush.
Why it is true
Facial blushing is a complex emotional response associated with self-awareness, dilating facial blood vessels.
Source: Psychology Research
Would you rather be asked first?
This is the reading side of the site, so the answer is in the sentence above — that is the whole point of it. Test yourself works the other way round: the question comes on its own, and the fact and the explanation only appear once you have answered.