Task: Question Answering
Input (English): Problem: the number of stamps that p and q had were in the ratio of 5 : 3 respectively . after p gave q 10 stamps , the ratio of the number of p ' s stamps to the number of q ' s stamps was 9 : 7 . as a result of the gift , p had how many more stamps than q ? 
Options: a ) 20 , b ) 30 , c ) 40 , d ) 60 , e ) 90
Output (English): a