Which element is required by plants in large quantities?

Minerals known to be required in large amounts for plant growth include

Which of the following elements is not required by plants for their normal healthy growth?

$A$: Some mineral nutrients are essential.
$R$: They can be synthesized by the plants.

Which of the following is an essential mineral element that is not a constituent of any enzyme but stimulates the activity of many enzymes?

Nitrogen is a critical element of the ecosystem because it is