 Of these, the best are merely slow such as 1.c3, 1.d3, and 1.e3.Worse possibilities either ignore the center and development such as 1.a3, weaken White's position (for instance, 1.f3 and 1.g4), or place the knights on poor squares (1.Na3 and 1.Nh3).Black has twenty possible responses to White's opening move.