Konstantin1983
chetan2u
The average income for a person with a bachelor of arts degree is several thousand dollars per year higher than somebody with a high school diploma only.
What is being compared?? :- the average income
(A) than somebody with a high school diploma only
Average income is compared with somebody
(B) than that for somebody with only a high school diploma
THAT stands for ' the average income' and the choice correctly compares the average income of two groups
(C) than for somebody with a high school diploma only
wrong comparison
(D) than it is for somebody with a high school diploma only
Illogical... IT stands for 'the average income ..... degree'
(E) that that of somebody having only a high school diploma
Parallelism issue
B
Hi
chetan2u!
Are you sure that in D "it" stands for "average income...degree"? Seems that "it"="that" and if you are right than B doesn't make sense

Hi..
When we are comparing, look at the portion that is common between the two and then work out comparison..
In D
(D) than it is for somebody with a high school diploma only..
It IS for somebody..
Look for IS in the non underlined portion..
The average income for a person with a bachelor of arts degree IS several thousand dollars per year
So IT equals " The average.....arts degree"
But in B THAT is before FOR
And what is there before FOR in non underlined portion- the average income
So THAT equals " the average income"
Hope it clears the ambiguity