The commutative property of addition states that changing the order of the numbers being added does not change the sum. Mathematically, this is expressed as \( a + b = b + a \).
Among the options provided:
a. \( 123 + 456 = 579 \) — This statement is incorrect as \( 123 + 456 = 579 \) is a true mathematical equation, but it does not demonstrate the commutative property.
b. \( abc + xyz = xyz + abc \) — This correctly demonstrates the commutative property of addition, as it shows that the order of the terms can be switched without changing the sum.
c. \( 0 + 579 = 579 \) — This statement is true, but it does not demonstrate the commutative property.
d. \( abcxyz = zyxcba \) — This is not relevant to the commutative property of addition.
Therefore, the correct answer is b. \( abc + xyz = xyz + abc \).