On November 2, 1772 , amid rising tensions with Great Britain, Boston colonists formed the Boston Committee of Correspondence. By 1774, what had started as a local means of mobilizing support for the Patriot cause had grown into something far more __ network of such committees that, facilitating communication among the colonies, helped lay the groundwork for the Continental Congress. Which choice completes the text so that it conforms to the conventions of Standard English? A. extensive: a B. extensive; a C. extensive, it was a D. extensive. A

## Step 1<br />The sentence is discussing the growth of the Boston Committee of Correspondence from a local means of mobilizing support for the Patriot cause to something far more. The word that completes the sentence should indicate a contrast between the local committee and the broader network of committees.<br /><br />## Step 2<br />Option A ("extensive: a") uses a colon, which is typically used to introduce a list, explanation, or example. In this context, it doesn't fit because the sentence is not introducing a list or an explanation.<br /><br />## Step 3<br />Option B ("extensive; a") uses a semicolon, which is used to connect two independent clauses that are closely related. This doesn't fit the sentence because the second part is not an independent clause.<br /><br />## Step 4<br />Option C ("extensive, it was a") uses a comma followed by a subject and verb, which would make the sentence a comma splice. A comma splice occurs when two independent clauses are joined by a comma without a coordinating conjunction.<br /><br />## Step 5<br />Option D ("extensive. A") uses a period, which is used to end a sentence. The second part of the sentence starts with "A" and is a complete sentence on its own, making it the correct choice.