Answer:
D. ab=ab
Explanation:
Communitive property of addition is a number plus a number and the number added to the first number backwards but equal the same answer. For instance (if you don't understand what I'm saying) Look at answer A in your problem, a+b=b+a that's how the communitive property works in addition. The rest of the answer choices also shows communitive property. This is why answer D does NOT show the communitive property in addition.
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