Task: Question Answering
Input (English): Problem: the compound interest earned by sunil on a certain amount at the end of two years at the rate of 10 % p . a . was rs . 420 . find the total amount that sunil got back at the end of two years in the form of principal plus interest earned . 
Options: a ) rs . 2530 , b ) rs . 2430 , c ) rs . 2420 , d ) rs . 2410 , e ) rs . 2440
Output (English): c