EVENT
BOARDSIZE 19
SETUP W D16 D4 K4 
SETUP B Q3 Q9 Q16 K16 
MARK C@D10 A@O17 B@R14
COM
Problem 71. White to play.  

Where should White play in this position ? Should she make an
approach move at one of the points A or B, or should she map
out a moyo at C ? 
ENDCOM
W 1 R14
MARK \t@K16 \t@Q9
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

White should approach with 1. The marked stone on the right is
more widely spaced than the one at the top, so White has more
room to expand.
<=
ENDCOM
  VAR
  W 1 O17
  COM
  Failure.

  White 1 is in the wrong direction.
  ENDCOM
  B 2 P17
  W 3 O16
  B 4 Q14
  COM
  After 4, ...
  ENDCOM
  W 5 M16
  COM
  ... White has to play a narrow extension with 5.
  ENDCOM
  B 6 K14
  COM
  Black jumps out into the center with 6 and is satisfied.
  <=
  ENDCOM
  ENDVAR
  VAR
  W 1 D10
  COM
  Failure.

  Making a sanren-sei on the left side with 1 is quite appealing,
  but ...
  ENDCOM
  B 2 Q14
  COM
  ... 2 is too good a point to allow Black to take. With one move,
  Black solidifies his moyo in the top right.
  <=
  ENDCOM
  ENDVAR