## Core Concept
Identical twins, also known as monozygotic twins, originate from a single fertilized egg that splits and develops into two separate embryos. Since they come from the same DNA material, they share the same genetic makeup. However, minute differences can arise due to environmental factors or random mutations during development.

## Why the Correct Answer is Right
The correct answer, , involves **fingerprint analysis**. Fingerprints are unique to each individual, even identical twins. The formation of fingerprints is influenced by small differences in the womb environment, such as the position of the fetus and pressure on the fingers. This results in unique patterns of ridges and valleys on each person's fingertips, making fingerprints an effective method for distinguishing between identical twins.

## Why Each Wrong Option is Incorrect
* **Option A:** - This option is incorrect because **blood group** is determined by genetics and identical twins will have the same blood group.
* **Option B:** - This option is incorrect as **DNA fingerprinting** would show a nearly identical pattern for monozygotic twins, making it unsuitable for differentiating between them.
* **Option D:** - This option is incorrect because **physical characteristics**, while sometimes slightly different due to environmental influences, are not reliable for differentiation as they can be very similar and subjective.

## Clinical Pearl / High-Yield Fact
A key point to remember is that while identical twins share the same DNA, **epigenetic factors** and **environmental influences** can lead to subtle differences. Forensic science often relies on **fingerprint analysis** as a practical method to distinguish between individuals, including identical twins.

## Correct Answer Line
**Correct Answer: C. Finger printing.**