The best? It’s groundbreaking (4)

I believe the answer is:

pick

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'the best?' is the definition.
(the best possible pick or selection)

I cannot understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for pick that I've seen before include "Select - ground-breaking tool" , "hacker?" , "Select - implement" , "Pluck" , "Choice" .)

I've seen this clue in The Guardian.

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