This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Dental
Which of the following hardness test is not used for brittle material: 
Select and explain. 
A. Rockwell test., B. Brinell test., C. Both., D. None.
C: Both.
Answer: C: Both. 
Explanation: HARDNESS TEST

Knoop hardness test
Vicker’s/diamond pyramid test

Not for BRITTLE material 

Rockwell
Brinells