A Long Solenoid Is Surrounded by a Circular Coil

Multiple Choice

A long solenoid is surrounded by a circular coil. If the current changes in the solenoid, the emf induced in the coil as measured between the terminals of the coil is directly proportional to all of the following except

A) the number of turns in the solenoid.
B) the number of turns in the coil.
C) the radius of the coil.
D) All of the above are true.