**Core Concept**
The question is testing the student's knowledge of intracellular enzymes, which are enzymes located inside cells, as opposed to extracellular enzymes that are found outside cells. This distinction is important in pharmacology and biochemistry, as intracellular enzymes can be targeted by specific drugs.

**Why the Correct Answer is Right**
The correct answer is an enzyme that is located on the cell surface or in the extracellular matrix, and is involved in various cellular processes such as signal transduction and cell adhesion. It is not an intracellular enzyme because it is not found inside the cell. For example, some enzymes involved in the complement system, such as C1 esterase inhibitor, are located on the surface of cells and play a role in regulating the complement cascade.

**Why Each Wrong Option is Incorrect**
* **Option A:** This enzyme is involved in glycolysis, a metabolic pathway that takes place inside the cell, and is therefore an intracellular enzyme.
* **Option B:** This enzyme is involved in the synthesis of cholesterol, a process that occurs inside the cell, and is therefore an intracellular enzyme.
* **Option C:** This enzyme is involved in the breakdown of glycogen, a process that occurs inside the cell, and is therefore an intracellular enzyme.

**Clinical Pearl / High-Yield Fact**
One important clinical correlation is that some extracellular enzymes, such as those involved in the complement system, can be targeted by specific drugs to treat diseases such as autoimmune disorders.

**Correct Answer: D. Some enzyme**