Question

nitrogen used by plants is in the form of
a. nitrites
c. nitrous
oxide
b. nitrates
d. nitric
oxide

Explanation:

Plants primarily absorb nitrogen from soil in the form of nitrates ($\text{NO}_3^-$), which is a key nutrient for their growth. Nitrites ($\text{NO}_2^-$) are less commonly used directly, and nitrogen oxides (like nitrous oxide $\text{N}_2\text{O}$ or nitric oxide $\text{NO}$) are gaseous and not the main form taken up by plants.

Answer:

B. Nitrates