(;SZ[13]AB[cb]AB[cc]AB[cd]AB[dd]AB[ec]AB[fc]AB[gc]AB[gb]AB[ga]AB[eb]AW[bb]AW[bc]AW[bd]AW[ce]AW[de]AW[ed]AW[fd]AW[gd]AW[hd]AW[hc]AW[hb]AW[ha]AW[ea]AW[db]AP[goproblems]
(;B[ca]C[RIGHT])
(;B[dc];W[ca];B[da]C[ko, black can do betterCHOICE])
(;B[fa];W[ca];B[da];W[dc]C[CHOICE]))