Spoiler alert: The answer is below the line.
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The right answer is B. This choice correctly separates two independent clauses into two separate sentences by use of a period.
The right answer is NOT A because this is a comma splice.
The right answer is NOT C because this is a run-on sentence.
The right answer is NOT D because, although the semicolon correctly separates two independent clauses, the comma after hill is unnecessary, as hill prairies is a single noun phrase.