If x is a sum of all even integers on the interval 13...65 and y is their number, what is the GCD (x, y)? Choose the correct choice from the following.
A) 1	B) 13	C) 26	D) 52	E) 1014

Rationale: "x = 14 + 16 + . . . + 64 = ( largest + smallest ) / 2 * ( # of terms ) = ( 14 + 64 ) / 2 * 26 = 39 * 26 . gcd of 26 and 39 * 26 is 26 . answer : c ."
Answer: C