## Core Concept
The glomerular filtration barrier is selectively permeable, allowing small molecules like water, ions, and glucose to pass through while restricting larger molecules like proteins and blood cells. The permeability of the glomerular membrane is primarily based on the size and charge of the particles.

## Why the Correct Answer is Right
The correct answer, , implies that the particle which is not charged or has a negative charge will pass more easily through the glomerular membrane. This is because the glomerular basement membrane has a negative charge due to the presence of sialic acid and glycosaminoglycans. Therefore, negatively charged particles are repelled, but neutral or positively charged particles can pass through more easily. Since both particles have the same diameter (size), the charge becomes a critical determinant of permeability.

## Why Each Wrong Option is Incorrect
* **Option A:** - This option suggests that a positively charged particle of a certain size would have an advantage, but without specifying its relation to charge and size compared to others, it's less directly relevant.
* **Option B:** - This option suggests size as a factor but does not account for charge, which is crucial for determining the ease of passage through the glomerular membrane.
* **Option D:** - This option implies that a larger size with a certain charge might have an advantage, which contradicts the premise that both particles have the same diameter.

## Clinical Pearl / High-Yield Fact
A key point to remember is that albumin, a negatively charged protein, is usually retained in the blood by the glomerular membrane, preventing its filtration into the urine. This selective permeability is crucial for maintaining proper blood composition and preventing proteinuria.

## Correct Answer: C.