A biofuel company finds that the yeast strain they have been using becomes less tolerant to ethanol. The company also notices that the "bad" yeast strain contains no dehydrogenase protein, which is involved in ethanol tolerance and is present in a normal yeast strain. Interestingly, the dehydrogenase mRNA in the "bad" yeast strain is the same as the one in a normal yeast strain. Which of the following might result in decreased ethanol tolerance in the "bad" yeast strain?
A. The promoter of the dehydrogenase gene in the "bad" yeast strain is absent.
B. The "bad" yeast strain has a mutated RNA polymerase.
C. Ribosomes in the 'bad' yeast strain are unable to bind to the dehydrogenase mRNA.
D. The dehydrogenase gene can't replicate in the "bad" yeast strain.