Product of two natural numbers is 17. Then, the sum of reciprocals of their squares is	Choose the correct choice:
A) 290 / 289	B) 1 / 289	C) 290 / 90	D) 290 / 19	E) none of these

Rationale: "explanation : if the numbers are a , b , then ab = 17 , as 17 is a prime number , so a = 1 , b = 17 . 1 / a 2 + 1 / b 2 = 1 / 1 ( 2 ) + 1 / 17 ( 2 ) = 290 / 289 option a"
Answer: A