If a measure is reliable, then a researcher must find a:

A) high positive correlation coefficient between scores on the measure.
B) negative linear relationship between the two variables being studied.
C) correlation coefficient of zero.
D) low amount of true score.

If a measure is reliable, it means that it consistently measures what it is designed to measure. This consistency is reflected in a high positive correlation coefficient between scores on the measure, meaning that individuals who score high on the measure tend to score high on subsequent administrations of the measure, and those who score low tend to score low. A negative linear relationship or correlation coefficient of zero does not necessarily indicate reliability, and low true score indicates poor reliability.