Target proteins which a drug molecule binds are:

The correct answer is (d) All of the above.

Drug molecules can bind to various target proteins, including:

– (a) Receptors: Proteins that receive and respond to signals, such as hormones, neurotransmitters, or growth factors.
– (b) Ion channels: Proteins that regulate the flow of ions across cell membranes, influencing electrical activity and cellular function.
– (c) Carriers: Proteins that transport molecules across cell membranes, such as transporters for nutrients, waste products, or ions.