Which school among the following upholds perception as an
unerring knowledge of the unique particular?

The correct option is Buddhism.

In Indian philosophy, the nature of perception (Pratyaksha) is conceptualized differently across various schools. In Buddhist epistemology, particularly as formulated by the eminent logicians Dinnaga and Dharmakirti, perception is defined as:
Kalpanapodham abhrantam (perception is free from conceptual reconstruction and is unerring/non-erroneous).

To understand why this definition aligns with Buddhism, we can analyze the key components of Buddhist epistemology:

1. The Two Types of Existents (Objects of Knowledge):
Buddhist philosophy divides all objects of knowledge into two distinct categories:
- Svalaksana (The Unique Particular): This refers to the real, momentary, indivisible, self-characterized thing-in-itself. It is localized in space and time, possesses causal efficiency, and represents ultimate reality (Paramartha Sat).
- Samanyalaksana (The Universal/General Character): This refers to the generalized features or concepts (such as class, name, or quality) that the mind constructs to group things together. It is a mental construction (Vikalpa) and is only conventionally real (Samvriti Sat).

2. Pure Sensory Perception:
In Buddhism, true perception is strictly non-conceptual. It occurs at the first moment of sensory contact, before the mind has time to name, categorize, or associate the sensation with past memories. Because it is completely free from conceptual thought (Kalpanapodham), it presents the object exactly as it is in its unique, momentary state.

3. Unerring Nature (Abhranta):
Since errors, illusions, and distortions are introduced only when the intellect begins to organize, name, and categorize sensory data (conceptualization), the pre-conceptual stage of pure sensation is completely free from error. Therefore, Buddhism holds that perception is the unerring knowledge of the unique particular (Svalaksana).