[单选题]
The primary of a transformer has 100,tr-x 0 hf/hhs tuaz ir98vbg+ h-rns and its secondary has 200 turns. If the power input to the primar r9hvi g8+z-bay is 100 W, we can expect the power output of the secondary to be (neglecting frictional losses)
A. 50 W.
B. 100 W.
C. 200 W.
D. none of the given answers
