is the most plausible move, but
is the tesuji for w and white can make two eyes at a.
So b should find a way to prevent two eyes at a by sente.
unkx80: I seem to recall reading somewhere that is the best resistance, and as a result, the best Black can do is to capture the
stones and let White live.
shevious: The number 8 in the title means that number of white stones were eight.
Go Seigen said that "the original is incomplete, so Utaro added three stones."
The flaw occurs in hhw's variation. Unlike the above variation, white is alive in the original problem.
unkx80: Thanks shevious. I posted that variation in a hurry without verification, and now I am caught with my pants down.
shevious: Your recalling was almost correct and quite helpful. I didn't realize the flaw of the original shape until you and hhw commented about the variations.