Why Should Tests Include a Items from a Variety of Difficulty

Multiple Choice

Why should tests include a items from a variety of difficulty levels?

A) Students are less likely to guess when there is a wide range of item difficulty.
B) Good tests encourage students to do their best and a range of difficulty helps less confident students.
C) Good tests discriminate at a variety of difficulty levels.
D) Students like to have some easy items because they are more likely to respond correctly by chance.