Refer to the Figure Showing the Expression of the Hoxb

Multiple Choice

Refer to the figure showing the expression of the Hoxb gene cluster in a mouse. Based on the figure, you can conclude that

A) determination of anterior structures is dependent upon expression of Hoxb1 and Hoxb2 genes.
B) Hoxb1 is expressed later in development than Hoxb9.
C) each Hoxb gene is expressed in a unique region along the anterior-posterior axis in which other Hoxb genes are not expressed.
D) there is greater Hoxb3 expression in the posterior than in the anterior region of the embryo.
E) Hoxb9 is the only Hoxb gene expressed in the anterior region of the embryo.