Which sentence uses a dash correctly?

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Answer:
(っ◔◡◔)っ ♥ The answer is: C. Roland glanced over his shoulder — John was following him! ♥
Explanation:
, , . , " ": ℝ ... . , , ' . ' , . , , ' , , .
Answer:
C. Roland glanced over his shoulder - John was following him!
Explanation:
This is the correct answer, because that sentence has two independent clause