(
; AB [ah][ba][bh][ca][cb][ch][dc][dg][dh][ec][ed][ee][ef] AW [bb][bc][be][bg][cg][dd][de][df] LB [bj:1][cj:2][dj:3][ej:4] C [Black plays first. What is the best possible result that black can guarantee? (1) Kill (2) Ko (3) Seki (4) Nothing][FORCE]
(
; B [bj]; W [bj] C [Demonstrate.]
(
; B [cd]; W [cc]
(
; B [ag]; W [bd]
(; B [ae]; W [ad]; B [ab]; W [af]; B [cf]; W [ce]; B [bf] AB [al][bs][bl][cs][cr][cl][dq][dm][dl][eq][ep][eo][en] AW [br][bq][bo][bm][cm][dp][do][dn]; W [bj] C [Now kill the symmetrical position at the bottom. White will play a different defense.]; B [cp]; W [co] (; B [bn]; W [an]; B [am]; W [cn]; B [bp]; W [cq]; B [ap] C [RIGHT])(; B [am]; W [bn])(; B [cq]; W [bp]))
(; B [ab]; W [ae]; B [ac]; W [af]; B [cf]; W [ce]; B [bf] AB [al][bs][bl][cs][cr][cl][dq][dm][dl][eq][ep][eo][en] AW [br][bq][bo][bm][cm][dp][do][dn]; W [bj] C [Now kill the symmetrical position at the bottom. White will play a different defense.]; B [cp]; W [co] (; B [bn]; W [an]; B [am]; W [cn]; B [bp]; W [cq]; B [ap] C [RIGHT])(; B [am]; W [bn])(; B [cq]; W [bp]))
(; B [af]; W [ae])
(; B [ce]; W [cf])
(; B [cf]; W [ce])
)
(; B [af]; W [bd] (; B [ae]; W [ad] (; B [ab]; W [ag])(; B [ag]; W [ab])(; B [ce]; W [cf]))(; B [bf]; W [ae])(; B [ag]; W [ae])(; B [ce]; W [cf])(; B [cf]; W [ce]))
(; B [bf]; W [af])
(; B [ae]; W [af])
(; B [ab]; W [bd])
(; B [bd]; W [ad])
(; B [ce]; W [cf])
(; B [cf]; W [ce])
)
(; B [af]; W [bf] (; B [ag]; W [ae])(; B [cd]; W [ce]))
(; B [ag]; W [cd])
(; B [bf]; W [af])
(; B [ab]; W [cc])
)
(; B [cj]; W [cj] C [Actually, black can kill without ko.])
(; B [dj]; W [dj] C [Black can do better than a seki.])
(; B [ej]; W [ej] C [Black can do better than nothing.])
)