In allocating free frames to the processes having different sizes which is measured in terms of number of pages as :
Logical address space of a process = No of pages * Page size
So more the number of pages of a process , the more priority it needs to be given..So for this we have proportional allocation technique which gives free frames according to the fraction of the total number of pages which is allocated to all the processes.
So here fraction of page occupied by process 1 = 10 / (10 + 5) = 2 / 3
Total number of frames = 50
So frame allocated to process 1 = 2 / 3 * 50
= 100 / 3
= 33
Similarly frames allocated to process 2 = 1/3 * 50
= 16 (approx)
So B) is the correct option.