POSTFIX EVALUATION ALGO
1) push the operands in stack when operator X comes take top 2 values say A and B and perform B X A and store the result at top of stack
2)Repeat the procedure till end of expression
here push 8 3 4 now +comes 3+4=7 stack now contains 8 7 now - comes so 8-7=1 stack now has 1
push 3 8 2 now / comes perform 8/2=4 then +comes 3+4 =7 stack now has 1 7 then * comes stack now has 7*1=7
now push 2 $ (power )comes perform 7^2=49 push 3 +comes stack now has 49 3 perform 49+3=52
hence final ans is D