(;
AB[pc][qd][pf][md][cp][iq][pq][oo]
AW[dd][eq][ld][me][ne][oc][po][qq]
TR[qq]
C[Black's response to the marked stone?

Source:
    "Go World", #29, Autumn 1982, pp. 53-58.]
(;
B[op]
C[Correct.
Black emphasizes the bottom and treats
the right side lightly.];
W[pn];
B[on];
W[pm];
B[qr];
W[qp];
B[dq]
C[With sente Black attacks the lower left stone.
Black's lone lower center stone becomes both
an excellent extension and pincer.];
W[ep];
B[dn];
W[ho];
B[jp];
W[jo];
B[ko];
W[jn];
B[gq];
W[fo];
B[dl]
C[Black has solid territory at the bottom,
good shape on the left, and a White group
to attack.]
)
    (;
    B[pn]
    C[Poor judgement.];
    W[pp];
    B[op];
    W[oq];
    B[pr];
    W[qr]
    (;
    B[ro];
    W[or];
    B[qp];
    W[ps];
    B[pq];
    W[lq]
    C[Now the Black lower middle stone has less
use as a pincer and no use as an extension.]
    )
        (;
        B[nq]
        C[Closing off White on this side does not
give Black full value for his sacrificed stones.];
        W[or];
        B[nr];
        W[ps];
        B[on];
        W[rn]
        C[And Black cannot keep White out of the
right side.]
        )
    )
    (;
    B[pp]
    C[A fighting move that does not work as
well as the correct move.];
    W[qp];
    B[qo];
    W[pn];
    B[ro];
    W[pr];
    B[qr];
    W[rr];
    B[rq];
    W[qs];
    B[rp];
    W[qr];
    B[nq];
    W[or];
    B[on];
    W[pm];
    B[ql];
    W[mq];
    B[op];
    W[nr]
    C[White links up and again Black's lower
middle stone is again made much less
effective.]
    )
)
