Answer:
What is the smallest sentence with all letters in the English alphabets?
What has a big mouth, yet never speaks?
What building has the most stories?
Though easy to spot, when allowed to plume, It is hard to see, when held in a room.
I am never quite what I appear to be. Straight-forward I seem, but it's only skin deep. For mystery most often lies beneath my simple speech. Sharpen your wits, open your eyes, look beyond my exteriors, read me backwards, forwards, upside down. Think and answer the question...
Black we are and much admired. Many seek us if they are tired. We tire the horse, and comfort man, and turn White when we've fulfilled your plan.