Discrimination index of a test item shows?

Discrimination index of a test item shows?
(a) How many answered wrong
(b) How well the item distinguishes between high and low achievers *
(c) How easy the test is
(d) How many dis-tractors are working

✅ Correct Answer: (b) How well the item distinguishes between high and low achievers
Explanation: A good test item has a high discrimination index, separating strong students from weak ones.