[单选题]
An n-type semiconductor is p6 m5cf8aku32r7e ew mk+f8v 9asn/cwj roduc7:ygjla6 jpr o95d + qg4b2bjued by
A. doping the host crystal with donor impurities.
B. doping the host crystal with accepter impurities.
C. pure crystals of germanium.
D. none of the given answers