## Core Concept
The Jones test, also known as the fluorescein test, is used to assess the patency of the nasolacrimal duct and canaliculi. It involves instilling fluorescein dye into the eye and then observing for its presence in the nasal cavity after a certain period, typically using a nasal swab. This test helps diagnose canalicular blockage.

## Why the Correct Answer is Right
In a normal Jones test, the fluorescein dye should be visible in the nasal cavity within a certain timeframe, indicating patent nasolacrimal ducts. However, in the case of canalicular blockage, the dye cannot pass through the canaliculi into the nasal cavity. Therefore, if the dye is not seen in the nose (or seen in decreased amounts) on the nasal swab after instillation, it suggests an obstruction. The correct answer relates to the expected outcome when canalicular blockage is present.

## Why Each Wrong Option is Incorrect
- **Option A:** This option might suggest a normal or expected finding in an unobstructed system, which does not align with the expected outcome in canalicular blockage.
- **Option B:** Similarly, this might propose an alternative explanation or outcome not directly related to canalicular blockage.
- **Option D:** This could represent another incorrect possibility, perhaps suggesting a different type of blockage or issue.

## Clinical Pearl / High-Yield Fact
A key point to remember is that in canalicular blockage, the Jones test will typically be **negative**, meaning the fluorescein dye will not be detected in the nasal cavity, indicating an obstruction preventing normal tear drainage.

**Correct Answer: C.**