4. 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 than (D) maybe it is none that was more concentrated than (E) perhaps none was more concentrated than
C It is none that is more ... is wordy; also, in this context, it must refer to something (unlike in phrases such as "it is clear that..."), yet it does not plausibly refer to anything. D As in C, it is none that was more ... is wordy; it must refer to something, yet it does not plausibly refer to anything.
OG是这么说的。。可是it is ...that 不是可以作为强调么。。去掉it is that之后变成none is more。。。。不就是E了么。。为什么wordy类。。。