Kyu Exercise 4 / Solution
The simpler solution would be a placement on the second line. forces , and reduces the eye at the bottom to one in sente.
Why sente? Because if White obstinately makes the other eye with , Black captures White with .
If simply captures the two Black stones, then cuts and captures two White stones.
If simply captures the two Black stones, Black can simply set up a snapback with and .
is incorrect. Although is a ploy to reduce the eye in sente, but answers correctly and lives.