Use the range rule of thumb to identify the values that are significantly low, the values that are signficantly high, and the values that are neither significantly low nor significantly high. A test is used to assess readiness for college. In a recent year, the mean test score was 19.5 and the standard deviation was 5.1. Identify the test scores that are significantly low or significantly high. What test scores are significantly low? Select the correct answer below and fill in the answer box(es) to complete your choice. A. Test scores that are less than . (Round to one decimal place as needed.) O B. Test scores that are between and . (Round to one decimal place as needed. Use ascending order.) O C. Test scores that are greater than . (Round to one decimal place as needed.)