[单选题]
A simple junction transistor consists of three 4 sob;kzmvm6-zm* 6izsemiconductor seu3g, 05np 3uxwsktwzhe e .x)1ctions consistingwnp0,3uh z)1x xstukewe3.5g of
A. pnp semiconductors.
B. npn semiconductors.
C. either pnp or npn semiconductors.
D. none of the given answers