At Medicago, scientists remove a specific genetic sequence that codes for a hemagglutinin protein from an influenza virus and insert this gene into an Agrobacterium genome. After the hemagglutinin gene is inserted into Agrobacterium, tobacco plants are infected with the Agrobacterium and the hemagglutinin gene is transferred into the tobacco plants. Which of the following allows the tobacco plants to express the hemagglutinin gene and produce the hemagglutinin protein?
Choose one or more:
A. the presence of a complete influenza virus genome in the tobacco plants.
B. a universal genetic code.
C. All living organisms produce at least low levels of the hemagglutinin protein.
D. promoters that allow the tobacco plants' RNA polymerase to recognize the gene.

The studies on the history of origin and evolution of life on Earth shows that all the organisms have evolved from a common descendant. This indicates that they possessed the same chemical-genetic or heredity molecule called Nucleic acid whether DNA or RNA.

DNA acts as the universal genetic material as it is present in all organisms except few. The process related to the DNA molecule is the same in all the organisms.

Since in the given question, the transfer of genes to plants via Agrobacterium and then the expression of the gene in plants shows that the passing of DNA has no barrier as DNA is the genetic material and the enzyme RNA polymerase recognized the gene which could help produce the mRNA from the gene.

Thus, options-B and D is the correct answer.