In the context of counseling research, which of the following is true of the measurement approaches based on the item response theory (IRT) ?

A) It is used to relate one's response patterns to items of similar levels of difficulty to determine the reliability of the test.
B) It is used to identify levels of how items measure a certain attribute.
C) It is used to assess the ability of scale items to measure present performance with prior performance.
D) It is used to examine whether particular scale items have varying levels of internal validity.

The item response theory (IRT) is used to identify levels of how items measure a certain attribute. It takes into account the difficulty level of individual items to understand how individuals respond to items and how well the items represent the underlying construct being measured. Option A is incorrect because IRT does not relate response patterns to items of similar levels of difficulty to determine the reliability of a test. Option C is incorrect because IRT is not used to assess the ability of scale items to measure present performance with prior performance. Option D is incorrect because IRT assesses the extent to which each item contributes to the measurement of the attribute being assessed, not the internal validity of the scale items.