Missy creates a personal budget. She enters her current savings account balance in cell D3. In cell A3, she calculates her income for the next three months. And in cell B3, she totals her expenses for the next three months. What formula should she use to calculate the money she will have in three months?

A =D3+A3-B3
B =D3+A3+B3
C =3-A3-B3=
D =D3*A3*B3