Which expression demonstrates the use of the commutative property of addition in the first step of simplifying the expression (–1 + i) + (21 + 5i)? (–1 + i) + (21 + 5i) + 0 –1 + (i + 21) + 5i (–1 + 21) + (i + 5i) –(1 – i) + (21 + 5i)