Task: Question Answering
Input (English): Problem: from january 1 , 2015 , to january 1 , 2017 , the number of people enrolled in health maintenance organizations increased by 13 percent . the enrollment on january 1 , 2017 , was 45 million . how many million people , to the nearest million , were enrolled in health maintenance organizations on january 1 , 2015 ? 
Options: a ) 38 , b ) 39 , c ) 40 , d ) 41 , e ) 42
Output (English): c