A ketose sugar is
a. Glucose
b. Fructose
c. Glyceraldehyde
d. Both A and B

Hint: The monosaccharide that consists of one ketone group per molecule is called ketose. Dihydroxyacetone is one of the simplest ketoses. It consists of only 3 atoms of carbon. No optical activity takes place in ketose. The ketose is a reducing sugar because through an aldol intermediate they tautomerize into aldoses.

Complete answer:
> Option B:
The monosaccharides or simple sugars that contain only one ketone group in its chemical structure is called ketose sugar. Some of the examples of ketose sugars are fructose, xylulose, and ribulose. One of the most important ketose sugar is fructose. To check that the sugar is reducing or not mainly two tests are used which are named Benedict’s and Fehling’s. The chemical test for separating ketoses and aldoses is Seliwanoff’s test. The non-reducing sugars in the ketose group are those which are bound with glycosides like fructose moiety of sucrose.

> Option A:
The subcategory of carbohydrate which is the most abundant monosaccharide is Glucose. The plants and most algae mainly form glucose during the process of photosynthesis from water and carbon dioxide. Most of the food we eat contains glucose and provides us energy. It is an aldose sugar.

> Option C:
The triose monosaccharide which is one of the simplest common aldoses is Glyceraldehyde. The taste of glyceraldehyde is sweet, colorless, and the structure is crystalline solid. It is used for polyesters and adhesives preparation, cellulose modifier, and also in the tanning of leather. It is also a source of nutrition.

Hence, the correct answer is option (B).

Note: Since far we have noticed that different sugars lie under a different group. The naturally available sugar which is present in fruits and honey is fructose and it is ketose sugar. It can also be called a caloric sweetener. The structure of fructose consists of one ketone group. The foods which contain a high amount of fructose are sauces, yogurt, baked foods, fast foods, etc.