Answer:
The current flows from the base to the emitter in the NPN transistor.
Step-by-step explanation:
NPN transistor : 
NPN transistor is a semiconductor in which the positively charged is sandwiched between two negatively charged. 
In NPN transistor, 
 is reverse-biases the collector-base junction and
 is reverse-biases the collector-base junction and 
 is forward- biases the emitter-base junction.
 is forward- biases the emitter-base junction. 
Hence, The current flows from the base to the emitter in the NPN transistor.