The function of a specific enzyme is most directly

The function of an enzyme is most directly influenced by its shape. The physical shape of an enzyme allows it to be connected to only one type of a molecule, the one that is compatible with the shape. Through the same it then  interacts with specific kinds of molecules, so its shape determines the function.

Option A, at mid-ocean ridges, is the correct answer.

The topmost layer of the nautical share of a tectonic plate is known as the Oceanic crust. The Ocean Ridge is created as an effect of raising up of magma from the asthenosphere. Mid-ocean ridges are a large, seismically activated submarine elevation system located in the center of the basin of an ocean and considering the situation of the up-welling of magma connected with seafloor expanding. Thus they are as thick as 6 Km at the mid-ocean ridges.