Establishment of the dorsal-ventral axis of the Drosophila embryo:

A)involves the production of localized DL mRNA on the ventral side of the developing embryo.
B)occurs via at least two paracrine signals transmitted between the developing oocyte and the surrounding somatic follicle cells.
C)involves the zygotically expressed DL morphogen.
D)depends on the activity of anterior-posterior morphogens,such as BCD or HB-M.
E)None of the answer options are correct.