**Core Concept**
The question tests the understanding of **glycolysis** and **gluconeogenesis**, two pivotal metabolic pathways. Glycolysis is the process of breaking down glucose to pyruvate, while gluconeogenesis is the synthesis of glucose from non-carbohydrate sources. Some enzymes are shared between these pathways.

**Why the Correct Answer is Right**
In glycolysis, the enzymes typically work in one direction, converting glucose into pyruvate. However, for gluconeogenesis, some of these enzymes are bypassed or work in reverse. One key enzyme that is part of both glycolysis and gluconeogenesis is **phosphoglucose isomerase**, but more notably, the correct answer involves considering which step is reversible or shared.

**Why Each Wrong Option is Incorrect**
**Option A:** Typically, the unique enzymes of glycolysis are not directly part of gluconeogenesis due to the need for bypass reactions in gluconeogenesis.
**Option B:** Similarly, this option might represent an enzyme specific to glycolysis without a direct role in gluconeogenesis.
**Option C:** This could be another enzyme specific to glycolysis.

**Clinical Pearl / High-Yield Fact**
A crucial point to remember is that **gluconeogenesis** uses some of the same enzymes as glycolysis but also involves unique bypass reactions to circumvent the irreversible steps of glycolysis, notably involving **pyruvate kinase**, **phosphofructokinase**, and **hexokinase** in glycolysis, which are bypassed in gluconeogenesis.

**Correct Answer:** D. Phosphoglucose isomerase, Enolase, and Pyruvate kinase are shared but phosphoglucose isomerase is the correct answer among the options given as it catalyzes a reversible reaction.