Answer:
it should be C) 2+1=3
Explanation:
the identity property is when zero is added to any number, or any number is multiplied or divided by 1, and in the end you get the original number.
Process of elimination:
5/1=5, so 5=5, that can't be the answer.
4x1=4. 4=4, that cant be the answer either.
3-0=3, and 3=3, thats also part of the identity property.
2+1=3, 2 does not =3,
therefore c is the only option not showing the identity property.