(;
GM[1]
SZ[19]
AW[dd][df][dq][md][nd][od][pc][qd][rd]
AB[pq][fc][jd][lc][mc][nc][qe][pe][pg]
LB[qk:A][qn:B][po:C]
C[Problem 119. Black to play.  

How should Black play on the right side: at A, B, or C ? ]
(;B[qk]
TE[2]
C[Correct Answer.  

Since it is a good idea to strengthen your weak stones, Black plays 1, the ideal move to defend his three stones in the upper right. It also works well with his stone below. ]
;W[co];B[jq];W[hq];B[ch]
C[The game continues to Black 5. <= ]
)
(;B[po]
C[Failure.  

If Black encloses the corner with 1, ... ]
;W[pj]
C[... White pincers with 2. ]
;B[ql]
C[Black 3 is a good move, but ... ]
;W[ok]
C[... White 4 prevents the black stones above from linking up with their allies below. They must flee, so White gets the initiative. <= ]
)
)