**Question:** Which of the following has highest electrophoretic mobility towards Anode

A. Positive ions
B. Negative ions
C. Neutral molecules
D. Negative ions

**Core Concept:**
Electrophoresis is a laboratory technique used to separate particles based on their electrophoretic mobility, which is determined by the particle's charge-to-size ratio. Particles with higher mobility, meaning they move faster towards the anode (positive electrode), will have a greater charge-to-size ratio.

**Why the Correct Answer is Right:**
D. Negative ions have the highest electrophoretic mobility towards the anode. This is because negative ions possess a greater charge-to-size ratio compared to other particle types. In an electric field, particles with a higher charge-to-size ratio move faster towards the anode.

**Why Each Wrong Option is Incorrect:**
A. Positive ions have a lower electrophoretic mobility towards the anode since their charge-to-size ratio is lower.
B. Negative ions, not positive ions, have the highest electrophoretic mobility.
C. Neutral molecules have no charge, so they do not exhibit electrophoretic mobility and cannot move towards the anode.

**Clinical Pearl / High-Yield Fact:**
Understanding electrophoresis is important in various clinical applications, such as DNA sequencing, protein analysis, and drug discovery. By separating molecules based on their electrophoretic mobility, scientists can study their functions, interactions, and roles in diseases.

**Correct Answer:** D. Negative ions