(;AP[goproblems]AB[sb]AB[sc]AB[rd]AB[qd]AB[pd]AB[pc]AB[nc]AB[ne]AB[nb]AB[lb]AW[sd]AW[se]AW[re]AW[qe]AW[pe]AW[rc]AW[qc]AW[qa]AW[pb]AW[oa]AW[na]AW[pg]TR[sc]TR[sb]C[Black to save the marked stones.](;B[ra];W[qb](;B[ob]C[White can't atari the black stones because she is short of libertiesCHOICERIGHT])(;B[ma];W[rb]C[White kills the Stones])(;B[sa]C[Wrong, this is not the bend four in the corner. White can escape])(;B[rb];W[sa])(;B[oc];W[rb]))(;B[rb];W[qb](;B[ob];W[ra]C[White kills])(;B[ma];W[ra]C[White kills]))(;B[qb];W[rb])(;B[ob];W[rb])(;B[ma];W[rb])(;B[sa];W[rb]))