Suppose we have a principally polarized abelian variety X over the complex number field. Also suppose given two effective divisors D_1, D_2 representing two ample line bundles in the same principle polarization.

Then is it true that D_1 and D_2 differ by a translation, i.e., there is x in X such that D_1 + x = D_2 as divisors? Why or why not?