Recognizing the Distinction Between Advances to Banks and the Nonborrowed

Recognizing the distinction between advances to banks and the nonborrowed monetary base,the money supply model is specified as ________.

A) M = m × (MBn - BR)
B) M = m × (MBn + BR)
C) M = m + (MBn - BR)
D) M = m - (MBn + BR)