(;
GM[1]
SZ[19]
AW[dd][jd][nc][dp][po][qp][qq][pm]
AB[pd][pf][pk][pq][jp][np][qr][rr]
LB[pm:1]
C[Problem 27. Black to play.  

This time White has tried a different tack by jumping along the fourth line with 1. What should Black do ? ]
;B[fq]
LB[qk:C][nm:B][nk:A]

TE[2]
C[Correct Answer.  

Black doesn't really have a convincing attack against the four white stones on the right. If he jumps to A, White will follow him out by jumping to B. Black's best move is to make an 'iron pillar' at C. However, White doesn't have any convincing moves here either. Therefore, it is best for Black to leave the situation as it is and switch to the left side by approaching with Black 1. <= ]
)
)