The correct option is
C negative charge moves from emitter to base
In n-p-n transistor, emitter (n-type) being heavily doped emits a large number of electrons, a few of which go into the base (p-type) for recombination with holes of the base whereas the rest of the electrons are collected by the collector (n-type).
Thus negative charge (electron) moves from emitter to base in n-p-n transistor.
![471896_231895_ans.png](https://search-static.byjusweb.com/question-images/toppr_ext/questions/471896_231895_ans.png)