(;GM[1]FF[4]CA[UTF-8]AP[CGoban:2]ST[2] RU[Japanese]SZ[19]KM[0.00]TM[] PW[White]PB[Black]AW[bb][cb][db][ac][bc][dc][dd][de][df]AB[ba][eb][gb][fc][ad][cd][ed][gd][be][ce][ff][bg][cg][dg][eg]LB[ba:1]C[black played 1. how to respond?]PL[W] (;W[aa]CR[aa] ;B[ab]CR[ab] (;W[ca]CR[ca]C[RIGHT black cannot connect: no ko]) (;W[da]CR[da] ;B[aa]CR[aa])) (;W[ca]CR[ca] ;B[aa]CR[aa]) (;W[da]CR[da] ;B[aa]CR[aa]) (;W[bd]CR[bd] ;B[aa]CR[aa]) (;W[cc]CR[cc] ;B[aa]CR[aa]) (;W[ec]CR[ec] ;B[aa]CR[aa] ;W[ee]CR[ee] ;B[fd]CR[fd] ;W[fe]CR[fe] ;B[ge]CR[ge]))