For a class of 30 students, the scores in a Mathematics test out of 10 marks were as follows; 4,5,7,2,3,6,5,5,8,9,5,4,2,3,7,9,8,7,7,7,3,4,5,5,2,3,6,7,7,2 What is the range of the distribution?

For a class of 30 students, the scores in a Mathematics test out of 10 marks were as follows;

4,5,7,2,3,6,5,5,8,9,5,4,2,3,7,9,8,7,7,7,3,4,5,5,2,3,6,7,7,2

What is the range of the distribution?

The correct answer is B. 7

No explanation given