A restrictive clause is one that


A. usually occurs at the beginning of a sentence.
B. limits the meaning of the word it describes.
C. should be set off by commas.
D. functions as an adverb.

B.

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The correct answer is B. A restrictive clause is one that limits the meaning of the word it describes.

To determine the correct answer, it is helpful to understand what a restrictive clause is and how it functions within a sentence.

A restrictive clause, also known as an essential clause or a defining clause, is a type of subordinate clause that provides essential information to the sentence. It is called "restrictive" because it restricts or narrows down the meaning of the word or phrase it modifies.

For example, consider the sentence: "The woman who is wearing a red dress is my sister." In this sentence, the restrictive clause is "who is wearing a red dress." It restricts the meaning of the word "woman" by specifying which woman the speaker is referring to.

Now let's go through the answer choices:

A. usually occurs at the beginning of a sentence:
Restrictive clauses can occur at different positions within a sentence, not just at the beginning. Therefore, this option is not correct.

B. limits the meaning of the word it describes:
This is the correct answer. As explained earlier, a restrictive clause provides essential information and restricts the meaning of the word or phrase it modifies.

C. should be set off by commas:
Unlike non-restrictive clauses, which are set off by commas, restrictive clauses do not usually require commas. They are considered necessary to the meaning of the sentence and are not set off by punctuation marks. Therefore, this option is not correct.

D. functions as an adverb:
Restrictive clauses do not function as adverbs. Instead, they function as modifiers that describe nouns or noun phrases. Therefore, this option is not correct.

In summary, a restrictive clause is one that limits the meaning of the word it describes. It does not necessarily occur at the beginning of a sentence, should not be set off by commas, and does not function as an adverb.