(;
AB[pb][oc][pd][qe][qf][qg]
AW[ob][nb][nc][nd][nf][pe][pf][qc]
TR[qc]
C[Black's response to White's marked play?

Source:
    Go World, #38, p. 52
    Tesuji problem, Yasuda Yasutoshi 4p]
(;
B[pc]
C[The worst.]
(;
W[qb];B[qd];W[pa]
C[White can link up to destroy Black's corner.]
)
    (;
    W[qd]
    C[Depending on the balance of ko threats, White might be able to make even more profit.];
    B[qb];W[rb];B[ra];W[sb];B[rd];W[rc];B[se];W[od];B[sc]
    C[And White takes the ko first.]
    )
)
    (;
    B[qb]
    C[Correct]
    (;
    W[pc];B[rc]
    C[Black gives up a stone to save most of the corner.]
    )
        (;
        W[qd]
        C[Too greedy.];
        B[rd];W[rc];B[rb];W[re];B[sc];W[sd];B[sb]
        C[Black captures White outright.]
        )
    )
)

