In a classic experiment from the 1970s investigating gene expression, a solution containing equal amounts of rabbit a-hemoglobin mRNA and b-hemoglobin mRNA, which encode subunits of a protein found in red blood cells, was injected into newly fertilized frog eggs. The injected mRNA was not degraded during the course of the experiment. Tadpoles that developed from the injected eggs were dissected into two fragments, one containing predominantly the notochord, muscle tissue, and nerve tissue and the other containing predominantly the other tissue types.
Equal amounts of total protein were analyzed after separation by electrophoresis to identify the relative amounts of the different proteins present in each sample. The thickness of the bands indicates the relative amounts of rabbit a-hemoglobin, B-hemoglobin, and frog tubulin (a cytoskeletal protein that is expressed at relatively constant levels in all tissues) present in each tadpole sample. The experimental protocol and results are summarized in the figure.

The observation that the rabbit mRNA was successfully translated in the frog tissues supports which of the following conclusions?

a) Frog cells are able to replace their own hemoglobin with rabbit hemoglobin.
b) Undeveloped frog eggs can be induced to form genetically identical copies of a rabbit.
c) Rabbit hemoglobin can induce an immune response in frogs.
d) Rabbits and frogs share a common genetic code for expressing heritable information.