(;AB[gb]AW[fb]AB[gc]AW[fc]AB[gd]AW[ec]AB[fd]AW[ed]AB[hd]AW[ee]AB[he]AW[fe]AB[ie]AW[ge]AB[jd]AW[gf]AB[jc]AW[hf]AB[ic]AW[if]AB[ib]AW[hg]AB[ia]AW[ih]AB[jf]AW[ii]AB[jg]AW[ji]AB[ig]AW[ki]AB[jh]AW[je]AB[kh]AW[ke]AB[lg]AW[kd]AB[li]AW[kc]AB[mi]AW[lc]AB[me]AW[mb]AB[md]AW[nb]AB[mc]AW[ob]AW[nc]AB[nd]AW[jb]AB[oc]AW[ka]AB[pb]AW[dd]AB[pd]AW[oa]TR[oa]C[White thinks this move makes him alive. Show him the truth.CHOICE]AP[goproblems]
(;B[ma]
(;W[la]C[CHOICE]
(;B[kb]
(;W[lb]C[CHOICE];B[ja]C[RIGHT])
(;W[ja]C[CHOICE];B[lb]C[RIGHT]))
(;B[ja];W[kb]C[CHOICE]))
(;W[kb]C[CHOICE];B[la]C[RIGHT])
(;W[ja]C[CHOICE]
(;B[la]C[RIGHT])
(;B[lb]
(;W[la]C[CHOICE];B[kb]C[The group is killed but playing M19 instead of M18 is betterRIGHT])
(;W[kb]C[CHOICE];B[la]C[Dead shape but playing M19 instead of M18 is still betterRIGHT])))
(;W[lb]C[CHOICE]
(;B[ja]C[RIGHT])
(;B[la]
(;W[na]
(;B[ja]C[RIGHT])
(;B[la];W[ma]C[CHOICE];B[ja]C[It works tooRIGHT]))
(;W[ja];B[kb]C[RIGHT])))
(;W[na]C[CHOICE]
(;B[kb]
(;W[lb]C[CHOICE];B[ja]C[RIGHT])
(;W[la];B[ja]C[RIGHT]))
(;B[lb];W[la];B[ja];W[kb])
(;B[ja]
(;W[la];B[kb]C[RIGHT])
(;W[kb];B[la]C[RIGHT]))
(;B[la];W[lb]C[CHOICE]
(;B[ja]C[RIGHT])
(;B[la];W[ma]C[CHOICE];B[ja]C[It works tooRIGHT]))))
(;B[ja];W[kb]C[CHOICE]
(;B[ma];W[la]C[CHOICE])
(;B[la];W[ma]C[CHOICE]))
(;B[kb];W[lb]C[CHOICE]
(;B[ja];W[ma]C[Ko for life])
(;B[ma];W[ja]C[CHOICE]))
(;B[la];W[ma]C[CHOICE]
(;B[ja];W[kb]C[CHOICE])
(;B[kb];W[lb]C[CHOICE]))
(;B[lb];W[la];B[ja];W[kb])
(;B[na];W[ma]C[:) Nope]))
Pavel N