Answer:
(b) Are Voltage-gated channels
Explanation:
Transmitter gates ion channels are also called ionotropic neurotransmitter receptors as one or more parts of the ion channel serve as a receptor for specific neurotransmitters.
Binding of the specific neurotransmitter to the receptor stimulates the opening of the ion channels and allows the transmembrane transport of specific ion.
The voltage-gated ion channels are the ones that open and close in response to changes in the voltage across the plasma membrane.
For example, voltage-gated Na+ channels are opened in response to depolarization of the membrane only.
