**Core Concept**
High-performance liquid chromatography (HPLC) and gas chromatography (GC) are two fundamental analytical techniques used to separate, identify, and quantify the components of a mixture. Both HPLC and GC are based on the principle of partitioning a sample between two phases: a stationary phase and a mobile phase.

**Why the Correct Answer is Right**
HPLC involves the use of a liquid mobile phase that flows through a stationary phase, typically a solid or a liquid, to separate and analyze the components of a sample. In contrast, GC involves the use of a gas mobile phase that passes through a stationary phase, usually a solid or a polymer, to achieve separation. Both techniques rely on the different interactions between the sample components and the stationary phase to achieve separation.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it is too vague and does not provide any specific information about the differences between HPLC and GC.
**Option B:** This option is incorrect because it is not true that HPLC and GC are based on the same principle of partitioning a sample between two phases.

**Clinical Pearl / High-Yield Fact**
Both HPLC and GC are widely used in clinical and research settings to analyze the components of biological samples, such as blood, urine, and tissue. These techniques are essential for diagnosing and monitoring various diseases, including metabolic disorders, cancer, and infectious diseases.

**Correct Answer: C. Both HPLC and GC are based on the principle of partitioning a sample between two phases: a stationary phase and a mobile phase.**