Which is an equation for the given word problem?

After Nancy deposits her birthday gift of $20.00 into her savings account, her balance is $225.50.

Which equation can be used to find the amount, n, in her account before she made the deposit?

A.20.00 – n = 225.50

B.n – 225.50 = 20.00

C.n + 225.50 = 20.00

D.20.00 + n = 225.50