Which level of measurement is least used in educational psychology?

Correct option is C

The ratio scale is least used in educational psychology because many psychological variables, such as intelligence or motivation, lack a true zero point, which is a defining characteristic of ratio scales. Most educational measurements rely on nominal, ordinal, or equal interval scales.
Information Booster:
· Ratio scales require absolute zero, used in physical sciences.
· Educational psychology frequently uses ordinal (rankings) and equal interval scales (test scores).
· Nominal scales classify categorical data (e.g., gender, ethnicity).
· Ratio scales might apply to certain quantitative measures like reaction times.
Additional Knowledge:
· Ordinal scale: Measures relative ranking or order without equal intervals.
· Nominal scale: Used for categorizing or labeling variables without numerical value.
· Equal interval scale: Most common in test scoring, assumes equal intervals between points.