[单选题]
The primary of a tra:w8cvp 3fcdvvc+0b7 7a z ptc7nsfor*pjw(byqv 6f56ql a -ymer has 100 turns and its secondary has 200 turns. If the power input to the primary is 100 W, we can expect the power output of the secondary pwq ja(*- 6y65lyf vqbto be (neglecting frictional losses)
A. 50 W.
B. 100 W.
C. 200 W.
D. none of the given answers
