A. The bacterial protein has a different amino acid sequence that is more effective.
B. As the protein is introduced therapeutically, it transfers the HGH gene as well.
C. Larger quantities are available.
D. A gene cloned from mice, rather than from humans can be used.
E. The product can be administered by infecting a person with the recombinant bacteria.
Answer by Kutmasta
My guess is C.
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