If the simple interest on a sum of money for 2 years at 5% per annum is Rs. 50, what is the compound interest on the same sum at the rate and for the same time?  Select:	A) rs . 51.25	B) rs . 51.27	C) rs . 51.79	D) rs . 51.8	E) rs . 51.93

Rationale: "sum = ( 50 * 100 ) / ( 2 * 5 ) = rs . 500 amount = [ 500 * ( 1 + 5 / 100 ) 2 ] = rs . 551.25 c . i . = ( 551.25 - 500 ) = rs . 51.25 . answer : a"
Answer: A