Question: Suppose we define h(H, m) = E(m, H)h(H,m)=E(m,H). Then the resulting h(\cdot,\cdot)h(⋅,⋅) is not collision resistant: to build a collision (H,m)(H,m) and (H’,m’)(H’,m’) choose random (H,m,m’)(H,m,m’) and construct H’H’ as follows:
A: H’=D(m’, E(m,H))
B: H’=E(m’,D(m,H))
C: H’=E(m’,E(m,H))
D: H’=D(m’,D(m,H))
Please eliminate two incorrect options first, then think it step by step and choose the most proper one option.