Justify Step 3 of the Solution $x + 7 = 6$

Justify step 3 of the solution. $x + 7 = 6$ Original equation $( x + 7 ) + ( - 7 ) = 6 + ( - 7 )$ Step 1 $x + [ 7 + ( - 7 ) ] = 6 - 7$ Step 2 $x + 0 = - 1$ Step 3 x=-1 Step 4

A) Associative Property of Addition
B) Additive Inverse Property
C) Addition Property of Equality
D) Additive Identity Property
E) Cancellation Property of Multiplication