选集 = curated 'best of' (the editor selects). Compare with
全集 (quánjí, 'complete works' — everything) and
文集 (wénjí, 'collected writings' — usually all works of one author). 《
毛泽东选集》 (Mao Zedong Xuǎnjí, Selected Works of Mao Zedong) is the canonical example.