Using Statistical Techniques to Measure Variability, Which of the Following

Using statistical techniques to measure variability, which of the following is the correct definition for an interquartile range for an interpercentile range?

A) Only middle cases are used.
B) Extreme scores are excluded.
C) Extreme scores are excluded, only middle cases are used, and measures are lined up according to size
D) Measures are lined up according to size.