The statement that belongs to region X is option (d)
(d) The main charge carriers are negative electrons
The reason for the selection is as follows;
The given region marked X belong to the NPN Transistor that has the following characteristics
The NPN transistor consist of a P-Type semiconductor sandwiched between two N-Type semiconductors
The charge carriers in a NPN transistor are negative electrons, while the charge carriers in a PNP transistor are holes
NPN transistor is the most commonly used type of BPT transistor due to the high mobility of electrons compared to holes
Electrons are passed from the emitter to the collector in an NPN transistor
Therefore, the statement that belongs only of the region marked X is that the main charge carriers are negative electrons
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