WGU D440 Nutrition OA Exam
Questions and Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
Question 1
What is the body’s primary source of energy?
A. Vitamins
B. Carbohydrates
C. Minerals
D. Water
Correct Answer: B. Carbohydrates
Rationale: Carbohydrates are the body’s preferred and fastest source of energy.
Question 2
Which macronutrient is primarily used for muscle repair?
A. Carbohydrates
B. Protein
C. Fat
D. Fiber
Correct Answer: B. Protein
Rationale: Protein supports tissue growth and repair, especially muscle.
,Question 3
Which nutrient provides the most energy per gram?
A. Protein
B. Carbohydrates
C. Fat
D. Vitamins
Correct Answer: C. Fat
Rationale: Fat provides 9 kcal per gram, more than protein or carbs (4 kcal/g).
Question 4
Which vitamin is fat-soluble?
A. Vitamin C
B. Vitamin B12
C. Vitamin D
D. Vitamin B1
Correct Answer: C. Vitamin D
Rationale: Fat-soluble vitamins include A, D, E, and K.
Question 5
Which vitamin is water-soluble?
A. Vitamin A
B. Vitamin D
C. Vitamin E
D. Vitamin C
Correct Answer: D. Vitamin C
Rationale: Vitamin C and all B vitamins are water-soluble.
,Question 6
What is the main function of fiber?
A. Muscle building
B. Energy storage
C. Digestive health
D. Oxygen transport
Correct Answer: C. Digestive health
Rationale: Fiber supports bowel regularity and gut health.
Question 7
Which mineral is essential for oxygen transport?
A. Calcium
B. Iron
C. Sodium
D. Potassium
Correct Answer: B. Iron
Rationale: Iron is a key component of hemoglobin in red blood cells.
Question 8
Which organ produces bile?
A. Kidney
B. Liver
C. Stomach
D. Pancreas
Correct Answer: B. Liver
Rationale: The liver produces bile to help digest fats.
, Question 9
Where is most nutrient absorption completed?
A. Stomach
B. Small intestine
C. Large intestine
D. Esophagus
Correct Answer: B. Small intestine
Rationale: The small intestine absorbs most nutrients from food.
Question 10
Which nutrient helps build strong bones?
A. Vitamin C
B. Calcium
C. Iron
D. Glucose
Correct Answer: B. Calcium
Rationale: Calcium is essential for bone strength and structure.
Question 11
Which vitamin is important for blood clotting?
A. Vitamin K
B. Vitamin C
C. Vitamin B6
D. Vitamin D
Correct Answer: A. Vitamin K
Rationale: Vitamin K is required for clotting factor production.
Questions and Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
Question 1
What is the body’s primary source of energy?
A. Vitamins
B. Carbohydrates
C. Minerals
D. Water
Correct Answer: B. Carbohydrates
Rationale: Carbohydrates are the body’s preferred and fastest source of energy.
Question 2
Which macronutrient is primarily used for muscle repair?
A. Carbohydrates
B. Protein
C. Fat
D. Fiber
Correct Answer: B. Protein
Rationale: Protein supports tissue growth and repair, especially muscle.
,Question 3
Which nutrient provides the most energy per gram?
A. Protein
B. Carbohydrates
C. Fat
D. Vitamins
Correct Answer: C. Fat
Rationale: Fat provides 9 kcal per gram, more than protein or carbs (4 kcal/g).
Question 4
Which vitamin is fat-soluble?
A. Vitamin C
B. Vitamin B12
C. Vitamin D
D. Vitamin B1
Correct Answer: C. Vitamin D
Rationale: Fat-soluble vitamins include A, D, E, and K.
Question 5
Which vitamin is water-soluble?
A. Vitamin A
B. Vitamin D
C. Vitamin E
D. Vitamin C
Correct Answer: D. Vitamin C
Rationale: Vitamin C and all B vitamins are water-soluble.
,Question 6
What is the main function of fiber?
A. Muscle building
B. Energy storage
C. Digestive health
D. Oxygen transport
Correct Answer: C. Digestive health
Rationale: Fiber supports bowel regularity and gut health.
Question 7
Which mineral is essential for oxygen transport?
A. Calcium
B. Iron
C. Sodium
D. Potassium
Correct Answer: B. Iron
Rationale: Iron is a key component of hemoglobin in red blood cells.
Question 8
Which organ produces bile?
A. Kidney
B. Liver
C. Stomach
D. Pancreas
Correct Answer: B. Liver
Rationale: The liver produces bile to help digest fats.
, Question 9
Where is most nutrient absorption completed?
A. Stomach
B. Small intestine
C. Large intestine
D. Esophagus
Correct Answer: B. Small intestine
Rationale: The small intestine absorbs most nutrients from food.
Question 10
Which nutrient helps build strong bones?
A. Vitamin C
B. Calcium
C. Iron
D. Glucose
Correct Answer: B. Calcium
Rationale: Calcium is essential for bone strength and structure.
Question 11
Which vitamin is important for blood clotting?
A. Vitamin K
B. Vitamin C
C. Vitamin B6
D. Vitamin D
Correct Answer: A. Vitamin K
Rationale: Vitamin K is required for clotting factor production.
