State the conclusion based on the results of the test. According to the report, the standard deviation of monthly cell phone bills was $48.38 three years ago. A researcher suspects that the standard deviation of monthly cell phone bills is less today. The null hypothesis is rejected. Choose the correct answer below. OA. There is not sufficient evidence to conclude that the standard deviation of monthly cell phone bills is less than its level three years ago of $48.38. B. There is sufficient evidence to conclude that the standard deviation of monthly cell phone bills is different from its level three years ago of $48.38. C. There is sufficient evidence to conclude that the standard deviation of monthly cell phone bills is less than its level three years ago of $48.38.