Pronoun Refernce

IT as a pronoun: (Sahil)
Whenever, ‘it’ is used in a sentence, it should always refer to a
NOUN. If that noun is not present in the sentence, don’t use ‘it’. Also ‘it’ should
unambiguously refer to a single noun in the sentence. If unsure, replace the ‘it’ in
the sentence with the NOUN.

Example,
Under a provision of constitution that was never applied, congress has been
required to call a convention for possible amendments to document when asked
about it. (There is no noun, to which ‘it’ can refer to).

It V/S That:(Manhattan)
If "it" and "that" are used as a pronoun, how do I choose between them? For example,

The dictionary is very helpful; without it, I don't know what the word means at all.
The dictionary is very helpful; without that, I don't know what the word means at all.

On the gmat, and in formal written english in general, you can't use the so-called 'pointing words.' those are the four words 'this', 'that', 'these', and 'those', used by themselves as pronouns. big fat no-no. the second one of these two sentences is, therefore, incorrect. -- the above is of course not meant to say that those four words are forbidden in general. you can, of course, use 'this', 'that', 'these', and 'those' as adjectives (these people, that book, etc.), or in specialized constructions wherein parallelism lends them meaning (such as 'beethoven's symphonies were more revolutionary than were those of bach').

That That : (Spidey's)

The inhabitants of Somalia greeted the measures outlawing polygamy with a similar defiance that welcomed the prohibition of alcohol in the United States in the nineteen-twenties.

a. a similar defiance that welcomed
b. a similar defiance which welcomed
c. a similar defiance to what welcomed
d. a defiance similar to that which welcomed
e. the same defiance welcoming

In English, instead of saying something like "that that" we say "that which." For example:
Example;
The number we recorded this week is greater than the number that we recorded last week.

The number we recorded this week is greater than that which we recorded last week.
is preferable to
The number we recorded this week is greater than that that we recorded last week.

In this sentence
The number we recorded this week is greater than that which we recorded last week.
that = number
and
which = number


So in our sentence here, we want to say:

The inhabitants of Somalia greeted the measures outlawing polygamy with a defiance
that was similar to the defiance that welcomed the prohibition of alcohol in the United States in the nineteen-twenties.

Which VS Where

At Shiprock, New Mexico, a perennially powerful girls’ high school basketball team has become a path to college for some and a source of pride for a community where the household incomes of 49 percent of them are below the poverty level.
(C) where 49 percent of the household incomes are
(D) which has 49 percent of the household incomes
(E) in which 49 percent of them have household incomes

Generally "where" is used for physical locations - otherwise, we have to use a variant such as "in which." Other variants include "at which" and "for which." Both "where" and "in which" refer to the community, which has already been established as a physical location (Shiprock New Mexico), so we can use "where." We could also use "in which" - this just means "in the community" which is also grammatically correct. The key is that the only "in which" option given has a pronoun error, so I don't have a grammatically correct option that uses "in which." That leaves me with "where" by default. A, B, and E all have pronoun errors. D would have to have a comma before the which and the verb "has" makes the sentence awkward. The community doesn't "have" household incomes. The individual members of the community do.

re: your other question as far as we can tell from our rather extensive research, the gmat does not use 'which' without commas. if you have a modifier that is not preceded by a comma - i.e., an essential modifier - then you use 'that', not 'which'.


Misleading THAT
A letter by Mark Twain, written in the same year as The Adventures of Huckleberry Finn were published, reveals that Twain provided financial assistance to one of the first Black students at Yale Law School.
(C) A letter by Mark Twain, written in the same year that The Adventures of Huckleberry Finn was published,--Correct
(D) Mark Twain wrote a letter in the same year as he published The Adventures of Huckleberry Finn that
"that" at the end of answer D indicates that the adventures of bucklebbery Finn is what "reveals", not the letter.

EACH before/after plural nouns
each of the three channels broadcasts ......
three channels each broadcast ......