Which of the following is a simple carbohydrate?

• A. Lactose.
• B. Galactose.
• C. Fructose.
• D. All of these.

Answer: (D)

Verified step by step guidance

1. Step 1: Understand the definition of simple carbohydrates. Simple carbohydrates, also known as sugars, are composed of one or two sugar molecules. They are quickly digested and provide a rapid source of energy.
2. Step 2: Break down the options provided in the question. Lactose is a disaccharide (made of glucose and galactose), galactose is a monosaccharide, and fructose is also a monosaccharide.
3. Step 3: Recall that monosaccharides (like galactose and fructose) and disaccharides (like lactose) are both classified as simple carbohydrates because they consist of one or two sugar units.
4. Step 4: Analyze the question's phrasing. Since all the options (lactose, galactose, and fructose) meet the criteria for simple carbohydrates, the correct answer must include all of them.
5. Step 5: Conclude that the correct answer is 'All of these,' as all the listed options are examples of simple carbohydrates based on their chemical structure and classification.