(;
GM[1]
SZ[19]
AW[cc][je][pc][qe]
AB[dc][dd][df][cj][hd][jc]
LB[dc:1]
C[Problem 107. White to play.  

Against White's invasion, Black blocks with 1. How does White respond ? ]
(;W[bd]
TE[2]
C[Correct Answer.  

White 1 is the Correct Answer. ]
;B[bf]
C[Black confines White to the corner with 2, ... ]
;W[db];B[eb];W[bb];B[da];W[cb]
C[... but White lives up to 7. <= ]
)
(;W[cd]
C[Failure.  

White 1 is a bad move. ]
;B[ce]
C[Black blocks with 2 and, ... ]
;W[db];B[eb];W[cb];B[bd]
C[... after 6, White has no room to make two eyes. <= ]
)
)