Consider that white has 384 more ko threats than you and that keeping sente is quite nice
(;AB[pc]AB[qd]AB[qe]AB[rf]AB[rg]AB[sh]AB[si]AB[pb]AW[ob]AW[oc]AW[od]AW[pd]AW[pf]AW[pe]AW[qf]AW[qg]AW[qh]AW[ri]AW[rj]AW[nb]AB[re]AW[sj]AB[rh]AW[qi]AW[qb]C[And the best black answer is?]AP[goproblems]
(;B[qc];W[pa];B[rb];W[ra]
(;B[qa];W[nj]LB[ni:R]C[Respond the ko threat pleaseFORCE];B[ni];W[qb]
(;B[sc]C[Very good! Now you are alive and gained sente - white will have to protect his stones otherwise you could capture them by making a double ko at T19!RIGHT])
(;B[oa]C[NOTTHIS])
(;B[sb];W[rc]))
(;B[sc]C[Very good! Now you are alive and gained sente - white will have to protect his stones otherwise you could capture them by making a double ko at T19!RIGHT])
(;B[sb];W[rc]
(;B[rd]C[White keeps sente])
(;B[sc]C[And white can tenuki]))
(;B[rc]C[Gote]))
(;B[rb];W[qc];B[rc];W[pa]C[The loss of the two stones was too big]))
