Answer: Option C.
G - alpha subunits stimulating the production of second messenger
Step-by-step explanation:
Metabotropic receptor is a type of receptor in the Eukaryotic cells that exerts it's action by producing a second messenger. They do not change channels but they exerts it effect by binding and stimulating G protein to produce a second messenger. They can either close or open channels in cell membrane. They are found at the surface of the cells or vessicles.