Black can kill the white group, you have to find how. There is many differents solutions. You can explore them by using the "navigate solution" option once you try to solve the problem.
(;SZ[19]AW[ic]AW[jc]AW[id]AW[kd]AW[he]AW[ie]AW[je]AW[le]AW[if]AW[lf]AB[hb]AB[ib]AB[jb]AB[lb]AB[hc]AB[kc]AB[hd]AB[ld]AB[md]AB[ge]AB[me]AB[gf]AB[hf]AB[mf]AB[gh]AB[hh]AB[mh]AB[nh]AB[ii]AB[ji]AB[lj]C[Black have to kill the white group.]GM[1]FF[4]CA[UTF-8]AP[CGoban:2]ST[2]RU[Japanese]KM[0.00]PW[Blanc]PB[Noir]
(;B[kf];W[kg]
(;B[lg];W[ke];B[jg]C[ Now white have only 1 eye in K16. L14 is not an eye.RIGHT])
(;B[jg]
(;W[jf]C[CHOICE];B[lg]C[ Now white have only 1 eye in K16. L14 is not an eye.RIGHT];W[ke]C[Now white have only 1 eye in K16. L14 is not an eye.RIGHT])
(;W[lg]C[CHOICE];B[jf]C[ Now white can only have 1 eye in K16.the group in L14 cannot be eaten.RIGHT]
(;W[jh];B[ig])
(;W[ig];B[jh]))))
(;B[lg];W[kf]C[White is alive, the groupe have two eyes in K16 and L15.])
(;B[kg];W[kf]C[White is alive, the groupe have two eyes in K16 and L15.])
(;B[jf];W[jg]
(;B[lg];W[kf]C[White is alive, the groupe have two eyes in K16 and L15.])
(;B[kf];W[kg];B[lg];W[ke]C[White is alive, the groupe have two eyes in K16 and L14.]))
(;B[jg]
(;W[kf];B[jf]C[ Now white have only 1 eye in K16. L15 is not an eye.RIGHT])
(;W[jf];B[kf]
(;W[kg]C[CHOICE];B[lg];W[ke]C[ Now white have only 1 eye in K16. L14 is not an eye.RIGHT])
(;W[lg]C[CHOICE];B[kg]C[ Now white can only have 1 eye in K16.the group in L14 cannot be eaten.RIGHT]))))
