If n is a positive integer, then `(sqrt(3)+1)^(2n)-(sqrt(3)-1)^(2n)`
is
(1) an irrational number
(2) an odd positive integer
(3) an even positive integer (4) a rational number other than
positive integers
A. an irrational number
B. an odd positive integer
C. an even positive integer
D. a rational number other than positiveintegers