## **Core Concept**
The question tests knowledge of specific tests for detecting **ketohexoses**, a type of sugar. Ketohexoses are a class of monosaccharides that have a ketone functional group and six carbon atoms. The most well-known ketohexose is **fructose**.

## **Why the Correct Answer is Right**
The correct answer, **Seliwanoff's test**, is a specific test for detecting ketohexoses. This test involves the dehydration of ketohexoses to form a furfural derivative, which then reacts with resorcinol to produce a **red-colored** compound. This reaction is characteristic and specific for ketohexoses like fructose.

## **Why Each Wrong Option is Incorrect**
* **Option A:** Benedict's test is used to detect reducing sugars, not specifically ketohexoses. It can detect various types of reducing sugars, including glucose and fructose, but does not differentiate between them based on their structure.
* **Option B:** Molisch's test is a general test for carbohydrates, not specific for ketohexoses. It detects the presence of carbohydrates by producing a purple-colored ring.
* **Option D:** Fehling's test is also used to detect reducing sugars. Like Benedict's test, it does not specifically identify ketohexoses.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that **Seliwanoff's test** is particularly useful in differentiating between **fructose** (a ketohexose) and **glucose** (an aldohexose). This distinction can be clinically relevant in certain metabolic disorders.

## **Correct Answer:** . Seliwanoff's test