## Core Concept
Real-time PCR (Polymerase Chain Reaction) is a laboratory technique used to amplify and quantify specific DNA sequences. It is widely used in molecular biology for various applications, including gene expression analysis, genotyping, and detection of infectious diseases.

## Why the Correct Answer is Right
The correct answer, **C. Quantification of DNA**, is right because real-time PCR is specifically designed to monitor the amplification of DNA in real-time, allowing for the quantification of the initial DNA concentration. This is achieved through the use of fluorescent probes or dyes that bind to the amplified DNA, enabling the measurement of the amplification curve and calculation of the initial DNA concentration.

## Why Each Wrong Option is Incorrect
* **Option A:** Detection of RNA - While real-time PCR can be used to detect RNA by first converting it to cDNA using reverse transcriptase (RT-PCR), the technique itself is primarily used for DNA quantification.
* **Option B:** Sequencing of DNA - Real-time PCR is not used for DNA sequencing; it is used for quantification of specific DNA sequences.
* **Option D:** Cloning of DNA - Although PCR, including real-time PCR, can be used as a step in cloning procedures, it is not primarily used for cloning DNA.

## Clinical Pearl / High-Yield Fact
A key point to remember is that real-time PCR is highly sensitive and can detect small changes in gene expression levels, making it a valuable tool in diagnostics, such as detecting viral load in HIV patients or monitoring gene expression in cancer research.

## Correct Answer: C. Quantification of DNA.