[单选题]
The primary of a transu5y,bz/;dz qdrkarr m+ :wr.+former has 100 turnsz,i/hj b/ f6mq and its secondary has 200 turns. If the power inb/6 hqzj/im f,put to the primary 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
