If White lives unconditionally, please play at A.
If not, please play the sequence that kills the White stones.
(;AW[jc]AW[kb]AW[ka]AW[ia]AW[ha]AW[hb]AW[hc]AW[hd]AW[gd]AW[ge]AW[ie]AW[je]AB[ja]AB[ib]AB[kc]AB[lc]AB[lb]AB[gb]AB[gc]AB[fc]AB[fd]AB[fe]AB[ff]AB[gf]AB[hf]AB[if]AB[jf]AB[ke]AB[lf]LB[gi:A]C[Black to play. Please play at A (G11) if you think White cannot be killed.]AP[goproblems]
(;B[gi]C[Yes, White can live unconditionally. (Try to find out why.) In the game, Black played A as a ko threat. When White played B, White lost the ko and some stones.RIGHT]LB[kc:A]LB[jb:B])
(;B[la]C[CHOICE];W[jb]C[white lives.])
(;B[jd]
(;W[jb]C[White lives.CHOICE])
(;W[ic]C[White lives.CHOICE]))
(;B[jb];W[ic]LB[jb:a]LB[jd:b]C[White lives. a & b are miai.CHOICE])
(;B[ga];W[jd]C[White lives.CHOICE])
(;B[he];W[jd]C[White lives.CHOICE])
(;B[kd];W[jd]C[White lives.CHOICE])
(;B[ic];W[jd]C[White lives.CHOICE])
(;B[id];W[jd]C[White lives.CHOICE])
(;B[hi]C[NOTTHIS])
(;B[hh]C[NOTTHIS])
(;B[gh]C[NOTTHIS])
(;B[fh]C[NOTTHIS])
(;B[fi]C[NOTTHIS])
(;B[fj]C[NOTTHIS])
(;B[gj]C[NOTTHIS])
(;B[hj]C[NOTTHIS])
(;B[fa]C[NOTTHIS])
(;B[ea])
(;B[fb]C[NOTTHIS])
(;B[eb])
(;B[ma]C[NOTTHIS]))