Match List I with List II.

List I (Nutrient)	List II (Bio-Chemical Test)
A. Vitamin A	(I) Health-Adjusted Life Expectancy
B. Protein	(II) Population - Bed Ratio
C. Vitamin K	(III) Age-Specific Death Rates
D. Niacin	(IV) Incidence and Prevalence

Choose the correct answer from the options given below:
(a) a-IV, b-II, c-I, d-III (b) a-II, b-IV, c-I, d-III (c) a-III, b-IV, c-I, d-II (d) a-I, b-II, c-III, d-IV

Correct option is D

The correct matching of nutrients with their corresponding biochemical tests is as follows:
· (a) Vitamin A → (II) Serum Retinol Serum retinol levels are measured to assess Vitamin A status in the body. Vitamin A is essential for vision, immune function, and skin health. A deficiency can lead to night blindness and xerophthalmia.
· (b) Protein → (III) Thyroid-binding Pre-albumin Thyroid-binding pre-albumin (Transthyretin) is used as a marker for protein status and is essential for the transport of thyroid hormones. It is commonly measured in malnutrition and protein-energy malnutrition (PEM).
· (c) Vitamin K → (I) Prothrombin Time Vitamin K is crucial for blood clotting, and prothrombin time (PT) is used to evaluate its function. A prolonged PT indicates Vitamin K deficiency, which can lead to excessive bleeding and coagulation disorders.
· (d) Niacin → (IV) N-methyl Nicotinamide in Urine Niacin (Vitamin B3) deficiency causes pellagra, which presents with dermatitis, diarrhea, and dementia. Its status is assessed by measuring N-methyl nicotinamide levels in urine, as it is a metabolite of niacin excreted by the kidneys.