(;GM[1]FF[4]AP[Drago:4.22.03]SZ[19]CA[UTF-8]C[Black to play.]AB[ss][sr][sq][sp][rp][qp][qq][pq][oq][or]AW[ns][nr][nq][np][op][pp][po][qo][ro][so][rq][rr][qr]
(;B[rs]C[Correct.];W[os]
;B[ps]C[The black group is alive in seki.])
(;B[os]C[This is wrong.];W[rs]C[White plays here and either it is a dead shape or White gets an eye.]
(;B[ps];W[qs])
(;B[qs];W[ps])))
