(;AW[ab]AW[ba]AW[cb]AW[bc]AB[ad]AB[bd]AB[cd]AW[cc]AB[dc]AB[db]AB[dd]AW[ed]AW[eb]AW[ec]AB[fa]AB[ga]AW[ha]AW[hb]AW[hc]AW[hd]AW[fe]AW[gd]AW[gg]AB[ee]AB[ef]AB[dg]AB[df]AW[eg]AW[eh]AW[ff]AB[di]AW[ei]AB[cj]AW[hf]AB[id]AB[ic]AB[ib]AB[ia]AB[ie]AB[if]AB[ig]AB[kf]AW[fd]C[Black to get the best result]AP[goproblems]
(;B[ea]
(;W[da]C[CHOICE];B[ca]C[if W throws in like this B will be happy to get a ko.RIGHT])
(;W[ac];B[da]C[How White should respondRIGHT]))
(;B[ca];W[da];B[ea];W[ca]C[No good.])
(;B[da];W[ea]
(;B[ac];W[ca])
(;B[ca];W[ac]))
(;B[fb];W[da];B[ea];W[ca]))