Let the maximum marks of each subject be 100.
So, Total Mark in five subjects = 500.
Student gets 60% aggregate marks i.e. 60% of 500 = 300 marks.
10x + 9x +8x +7x +6x = 300
40x = 300
x = 300/40 = 7.5.
Marks in first subject = 10x = 10 *7.5 = 75.
Marks in second subject = 9x = 9 *7.5 = 67.5
Marks in third subject = 8x = 8 *7.5 = 60.
Marks in fourth subject = 7x = 7 * 7.5 = 52.5
Marks in last subject = 6 *7.5 = 45.
Thus, he passed in 4 subjects.
Option C is the Correct Answer.