The Proteins Dorsal and Bicoid Both Act as Morphogens in Drosophila

The proteins Dorsal and Bicoid both act as morphogens in Drosophila embryogenesis. However, the establishment of the concentration gradients of each protein differs. Which of the following statements CORRECTLY describes this difference?

A) The dorsal gene is transcribed maternally while the bicoid gene is transcribed in the developing embryo.
B) The dorsal gene is transcribed in the developing embryo whereas the bicoid gene is transcribed maternally.
C) The concentration gradient of Dorsal is established through asymmetric subcellular localization whereas the concentration gradient of Bicoid is established through selective degradation.
D) The concentration gradient of Dorsal is established through asymmetric subcellular localization whereas the concentration gradient of Bicoid is established through asymmetric localization of the bicoid mRNA and thus protein.
E) The concentration gradient of Dorsal is established through differential rates of translation whereas as the concentration gradient of Bicoid is established through a transport system.