(;AP[goproblems]AB[ic]AB[jc]AB[lb]AB[mb]AB[hb]AB[gb]AW[hc]AW[gc]AW[id]AW[jd]AW[kd]AW[lc]AW[mc]AB[fb]AB[ob]AW[nc]AB[nb]C[White to cut black.](;W[kc];B[kb])(;W[ib];B[kb])(;W[jb];B[kb](;W[ib];B[kc])(;W[kc];B[ib]))(;W[ka];B[kb])(;W[ia];B[kb])(;W[ja];B[kb])(;W[kb](;B[jb]C[CHOICE](;W[kc];B[ka])(;W[ja];B[ia](;W[kc];B[ka])(;W[la];B[ka]MA[ja]C[Ko. The connection at L19 instead of M19 prevents this.])(;W[ka]TR[kc]C[Correct. Black is short of liberties and cannot cut at L17.RIGHT]))(;W[ka];B[kc])(;W[la];B[kc]))(;B[ja]C[CHOICE](;W[kc];B[ka])(;W[ka];B[kc](;W[ib]C[RIGHT])(;W[jb];B[ib])(;W[ia];B[ib]))(;W[jb];B[ib](;W[kc];B[ka])(;W[ka];B[kc]))(;W[ib]C[];B[ka](;W[jb];B[ia])(;W[ia];B[jb]))(;W[ia];B[ib](;W[jb];B[kc])(;W[kc];B[ka])(;W[ka];B[kc])))))