Researchers Were Interested in Finding Out How the Respiratory Parameters

Researchers were interested in finding out how the respiratory parameters in a group of individuals who were diagnosed with asthma responded to a six-week aerobic training intervention. Forced expired ratio (FER, %) is the product of the forced expired ratio in 1 second (FEV₁, litres) divided by the forced vital capacity (FVC, litres) and was the parameter the researchers were most interested in. The results are presented below. Enter the data into SPSS and plot a bar chart representing the mean of the pre- and post-test data. Add the 95% confidence intervals for the mean. You should get the bar chart shown below. What does the 95% confidence interval (CI) that you have plotted refer to?

A) 95% confidence that the mean will fall between these intervals
B) 95% confidence that all data points fall between these intervals
C) 95% confidence that all data points fall outside these intervals
D) 95% confidence that the range falls between these intervals