The Average number of students scoring marks less than or equal to 60% is

In A, 40% of students scored above 60% marks, the number of them being equal to 1160. Hence, the total number of students is 2900.

In B, 30% of students scored above 60% marks, the number of them being equal to 1170. Hence, the total number of students is 3900.

In C, 50% of students scored above 60% marks, the number of them being equal to 1170. Hence, the total number of students is 2340.

In D, 15% of students scored above 60% marks, the number of them being equal to 1200. Hence, the total number of students is 8000.

In E, 40% of students scored above 60% marks, the number of them being equal to 1600. Hence, the total number of students is 4000.

The number of students scored less than or equal to 60% from A is 1740.

The number of students scored less than or equal to 60% from B is 2730.

The number of students scored less than or equal to 60% from C is 1170.

The number of students scored less than or equal to 60% from D is 6800.

The number of students scored less than or equal to 60% from A is 2400.

The sum of these numbers is 14840.

The average will be 14840/5=2986.

So, option B is the answer.