Talia is solving the following equation.
7x - 4 = 31

Which shows a step Talia can use to solve the equation?
A.
7x - 4 = 31 + 4
B.
7x - 4 + 4 = 31 + 4
C.
7x - 4 - 4 = 31 - 4
D.
7x - 4 = 31 - 4