Task: Question Answering
Input (English): Problem: if the simple interest on a certain sum of money for 6 years is one – fifth of the sum , then the rate of interest per annum is 
Options: a ) 3.3 % , b ) 7.2 % , c ) 6.1 % , d ) 5.0 % , e ) 3.1 %
Output (English): a