Identify the coordinating conjunction and its purpose in the following sentence.
Coordinating conjunctions can help a writer vary sentence structure, but they should not be used in every sentence.
A. The coordinating conjunction is but, and it is used to establish a connection between two phrases.
B. The coordinating conjunction is but, and it is used to connect two independent clauses and introduce an opposing idea.
C. The coordinating conjunction is but, and it is used to connect an independent clause to a dependent clause.
D. The coordinating conjunction is but, and it is used to connect two dependent clauses.