(;
AB[qb][pc][qd][qe][rf][rg][qg][qh]
AW[re][qf][pf][pg][pe][pd][oc][ob]
C[White plays.

Source:
    A problem from the endgame volume of Gokyo Seimyo, a nearly 200 year old problem set.]
(;
W[pb]
C[Vulgar.];
B[qc]
C[White loses the chance to take advantage of the bad corner aji.];
W[qa];B[ra];W[pa];B[sb]
C[White reduces the corner in sente, but could have done much better.]
)
    (;
    W[rd]
    C[Another ill-conceived plan.];
    B[qc];W[rb]
    C[White is a move behind to catch the Black stones.];
    B[rc];W[qa];B[pa]
    C[White has nothing.]
    )
    (;
    W[rb]
    C[Best!]
    (;
    B[qc]
    C[Black's connection looks good, but still leaves a weakness.];
    W[qa]
    TR[rb]
    C[Black cannot cut off the marked stone.];
    B[pa]
    C[For example ...];
    W[ra];B[pb];W[rd]
    C[... and Black collapses.]
    )
        (;
        B[rc]
        C[No better.];
        W[pb];B[qa]
        TR[rb]
        C[And if Black tries to cut off the marked stone, ...];
        W[qc]
        C[... White is happy to start this ko, in which Black risks losing quite a few more points in the corner.]
        )
    )
)

