First, let me tell you that there is a subtle difference between "perhaps" and "may be".
You can say "perhaps"(possiblly) holds 70% chances of happening whereas "may be" holds 30-40% chances of happening.
Now looking back to the questions:
Of all the major developments in information technology that have influenced literary production, maybe none is more influential as the printing press, which brought the entire classical canon to people throughout Europe within 60 years of its invention.
A maybe none is more influential as
B it may be that none is more influential as
C perhaps it is none that is more influential than
D maybe it is none that was more influential than
E perhaps none was more influential than "
The use of "perhaps" and "may be" entirely depends on the context.
I assume that you may have reduced the options to limit yourself to D and E.
What is wrong in E? "development is being compared to printing press
Of all the vast tides of migration that have swept
through history, maybe none is more concentrated as
the wave that brought 12 million immigrants onto
American shores in little more than three decades.
(A) maybe none is more concentrated as
(B) it may be that none is more concentrated as
(C) perhaps it is none that is more concentrated
(D) maybe it is none that was more concentrated
(E) perhaps none was more concentrated than
Here the construction of E is much much better than D. "May be it is none" sounds very awkward.
Note that correct comparison has to be made always. In the first question, if the correct comparsion had been made then E would have been the answer.
Prepositional Phrases Clarified|Elimination of BEING| Absolute Phrases Clarified
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