(;
AB[qn][rn][oo][op][po][mq][nq][pq][pr][ps][qq][lr]
AW[pp][qp][rp][oq][or][rq][nr][qr]
C[Black plays.];
B[rr];W[rs]
(;
B[sr]
C[A greedy mistake.];
W[os]
C[White has a snapback to capture 6 stones to live.]
)
    (;
    B[qs]
    C[Correct.  Black must defend here.];
    W[sr]
    C[This ko is the optimal result for both sides.  Note that both sides must make an approach move to win the ko.]
    )
)

