EVENT
BOARDSIZE 19
SETUP W D16 G16 E10 C10 C7 Q4 R6 
SETUP B C12 E12 G12 C4 F4 O3 Q16 
MARK A@J17 B@G10 C@K3
COM
Problem 122. Black to play.  

Should Black attack the two white stones at the top with A, attack
the three white stones on the left side with B, or strengthen
his position at the bottom with C ? 
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B 1 J17
USER
CORRECT ANSWER
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COM
Correct Answer.

The two white stones at the top are thin, so Black can take profit
by attacking them ...
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  VAR
  B 1 K3
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  Failure.

  Black 1 is certainly a big point, but ...
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  W 2 K17
  COM
  ... White 2 is even bigger. Black has lost the chance to seize
  the initiative at the top.
  <=
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  ENDVAR
W 2 H15
B 3 K15
W 4 H17
B 5 J16
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... with the sequence to 5.
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W 6 H18
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After White 6, ...
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B 7 C17
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... Black invades with 7. Because of the three black stones below,
White's stones will be under a lot of pressure.
<=
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