Question

If farmers grow the same crop on their soil every year they have to use fertilizer to replace essential nutrients in the soil. In order to use less fertilizer some farmers choose to rotate their crops by alternating with legumes such as beans. Rotating crops and using fertilizer replenish the soil with which essential element required for all living things? A. yttrium B. protein C. nitrogen D. glucose

Answer 1

The keyword is "element". Neither proteins, nor glucose are elements.

Answer 2

So then its nitrogen

Answer 3

yep. If you wanna take it further, list what molecules in the plant have nitrogen.