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(A)It's a distance that is so minute that comparing it to anything in the regular world is a bit of a joke.
(B)Nanotechnology matters because familiar materials begin to develop odd properties when they'renanosize.
(C)Nanotechnology has been around for two decades, but the first wave of applications is only nowbeginning to break.
(D)Not all nanosize materials can change properties so usefully, but the fact that some do is a boon.