The correct option is C 3
To find the number of chairs along shorter side we need to find the factors of 18.
Total number of chairs =18
Chairs in a single row = 6
Factors of 18 = 1, 2, 3, 6, 18
18 can be represented as:
1 x 18 , 2 x 9, 3 x 6
So, 3 such rows will be there in the classroom.