Answer:
B) identity property of addition.
Step-by-step explanation:
Given:
The statement given is:
[tex]10+a=10,\ then\ a=0[/tex]
Here, we observe that 10 is added to a giving the number 10 itself as the answer. So, we know of a property which says that when 0 is added to a number, the result is the number itself. This property is called identity property of addition.
So, the value of [tex]a[/tex] must be 0 because on adding [tex]a[/tex] to 10, we are getting the number 10 only. So, the above statement is an example of identity property of addition.