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Foam on a crest, 4 letters

Candy sampler pieces, 11 letters

A theory of strong interactions between elementary particles (including the interaction that binds protons and neutrons in the nucleus), 3 letters

It assumes that strongly interacting particles (hadrons) are made of quarks and that gluons bind the quarks together, 3 letters - we know the word that you can`t guess In case of any inconvenience..