Which of the Following Test Items Is Best (A, B

Multiple Choice

Which of the following test items is best (a, b, c, or d) , where p is the item difficulty index and D the item discrimination index?

A) p = .30, D = .50
B) p = .50, D = .50
C) p = .70, D = .20
D) p = 1.00, D = .50