FC0 is a (+) frameshift mutation in the rII locus. A stock of FC0 is mutagenized with proflavin and plated on a lawn of E. coli K, where only phenotypically wild type phage can grow. You pick one of the plaques and make a stock of it. You would like to determine whether the stocks reversion to rII+ was a true reversion or the result of a second site suppressor mutation. To do this you cross the phage with phage from a wild type stock and plate the progeny on E. coli B. You find that 96% of the plaques are small and 4% large. Based on this data, you conclude that the stocks reversion to rII+ was the result of: A. true reversion.
B. second site suppressing mutation

B. second site suppressing mutation

Explanation:

The second site of the repression mutation as 96 percent showed the small colonies that tells the growth was not the good as the agar that allowed the growth of the only wild type of strains. So it was not a true reversion to a wild type.

And because the small colony is visible, it means that there are some growth which means that some of the strains tried to turn back in the wild type.

the answer for this question would be d. glaciers

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.