IV.B.20.   The primary factor that limits the maximum MA that can be used during a radiographic exposure is:

    a.   Anode angle.

    b.   Focal spot size.    Correct.

    c.   Cathode temperature.

    d.   Exposure time.

    Discussion:   The cathode temperature is used to control the MA but is not usually the limiting factor.   Switching from the smaller to the larger focal spot size increases the maximum MA that can be used in a procedure.

    Reference:   Physical Principles of Medical Imaging, 2nd. Edition.   p. 244