Match List-I with List-II and select the correct answer:

List-I	List-II
a. Nitrogen	1. Structural element
b. Iron	2. Biocatalytical element
c. Molybdenum	3. Indispensable element
d. Iodine	4. Stimulating element

A. a-2, b-3, c-4, d-1

B. a-3, b-1, c-2, d-4

C. a-1, b-2, c-3, d-4

D. a-2, b-1, c-4, d-3

Answer: Option C