xy=1 then what is (5^(x+y)^2) / (5^(x-y)^2)
Choose the correct choice from the following choices
A) 2 B) 625 C) 8 D) 16 E) 32

Rationale: "( x + y ) ^ 2 - ( x - y ) ^ 2 ( x + y + x - y ) ( x + y - x + y ) ( 2 x ) ( 2 y ) 4 xy 4 5 ^ 4 = 625 answer b"
Answer: B