When an Item-Characteristic Curve of an Ability Test Has an Inverted

Multiple Choice

When an item-characteristic curve of an ability test has an inverted U shape,it usually indicates that

A) testtakers of moderate ability have the highest probability of answering the item correctly.
B) testtakers of low ability have the highest probability of answering the item correctly.
C) testtakers of high ability have the highest probability of answering the item correctly.
D) the item is working as well as any item on this test could be expected to work.