(;AW[ar]AW[br]AW[cr]AW[dr]AW[ds]AB[aq]AB[bq]AB[cq]AB[eq]AB[er]AB[es]AW[dp]LB[bs:A]LB[dq:B]C[Play in 'A' or 'B'.]AP[goproblems] (;B[bs];W[dq]C[you cannot kill w];B[bo];W[co];B[bn];W[bp];B[ao];W[cp];B[ap];W[cm]C[Black is now split into two weak groups (in fact, the one on the left side is already dead), where as White has escaped into the center. True, White is reduced to one eye in the corner, but White will live easily and profit greatly from Black's reckless attack.]) (;B[dq];W[bs]C[Correct! White lives with two points in the corner, but the black stones are connected, strong, and safe. This is a much better result than trying to kill the white stones (and failing).RIGHT]))