Use the following data to answer question 14-18 :
6, 0, 1, 2, 6, 8, 2, 1, 5, 1, 4, 9, 6, 1, 5, 6, 5, 6, 8, 6, 6.
The mode the mark is

• A.7
• B.6
• C.8
• D.5
• E.4