Aseries of enzymes catalyze the reactions in the metabolic pathway x → y → z → a. product a binds to the enzyme that converts x to y at a position remote from its active site. this binding decreases the activity of the enzyme. with respect to the enzyme that converts x to y, substance a functions as
a. an intermediate
b. a competitive inhibitor
c. an allosteric inhibitor
d. the substrate

The correct answer will be option-C

Explanation:

In the given question, product A can bind to the enzyme which can convert X to Y.

This product A can act as a non-competitive inhibitor which can attach to the site away from the active site. These compounds are known as allosteric inhibitors.

The allosteric inhibitors bind to the enzyme away from the active site and change the conformation of the protein which changes the conformation of the active site which prevent enzyme bind the substrate.

Thus, Option-C is the correct answer.

answer and explanation;

volcanic rocks are igneous rocks which form from lava, molten rock which has been thrust out of a volcano onto the surface of a rocky body such as an asteroid, planet, or dwarf planet.  

plutonic rocks are igneous rocks which form from subterranean chambers of molten rock or magma. plutonic rocks make up the base of continental crust as well as oceanic crust. their slow rate of formation causes them to be coarse grained since there is plenty of time for large crystals to form before the magma solidifies into rock.

the textural difference is that plutonic rocks are more coarse grained than volcanic rocks. plutonic rocks are coarse grained while volcanic are fine grained ; glassey or fragmental. since fine and coarse are adjectives the decision as to whether a rock is fine or coarse grained is generally made on the bases of whether or not the individual crystals can be seen in most if the rock.

not: both offer magnification to the atomic level.