75 - 40 = 35 students used just browser A;
18 students used just browser B;
40 students used both ( A and B );
7 students did not use either browser A or browser B.
35 + 18 + 40 + 7 = 100
100 students ------------- 58 use browser A
300 students --------------- x use browser B
x = 58 300 / 100 = 58 3 = 174
Answer: D ) 174