16. A transformer has 200 turns on the primary and 20 turns on the secondary. The primary is connected to a direct current source of 100 millivolts. The voltage in the secondary coil will be
A. 10 millivolts.
B. 20 millivolts.
C. 1000 millivolts.
D. 4000 millivolts.
E. zero.