Which property does the equation 4 + x +7 = 4 + 7 + x illustrate?

Question

A. Identity property of addition
B. distributive property
C. Commutative propert of addition
D. Associative property of addition

I think it's D.

Thank You.

Answer 1

I think it is C
look here right now:
http://www.coolmath.com/prealgebra/06-properties/01-properties-commutative-addition-01.htm

Answer 2

Thank You.

Answer 3

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