Chess Opening Theory/1. d4/1...Nf6/2. c4/2...c5/3. d5/3...e6/4. Nc3

=Modern Benoni= Knight c3 to support the central pawn advance of e4.

Theory table
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'''1. d4 Nf6 2. c4 c5 3. d5 e6 4.Nc3'''