Question

Choose the correct essentiality criteria for mineral element
A) Deficiency of any element can be met by supplying some other element
B) Element must be involved in the metabolism of the plant
C) Plant do not complete their life cycle without the element
D) Few elements have been found to be absolutely essential for growth of the plant

• A. A, B and C
• B. B and C
• C. A and C
• D. B, C and D

Hint:

Remember that "specificity of requirement" is a core tenet of mineral essentiality.
If element X is deficient, only element X can correct that deficiency. No other element can substitute.

Answer 1

The Correct Option is D

Step 1: Look at this from a testing angle.
Instead of memorising the definition, treat each statement like a true or false test using what mineral nutrition actually requires from an element.
Step 2: Check statement A.
If one element's job could be done by another, we would never see specific deficiency symptoms in plants. Since specific symptoms do appear and cannot be fixed by substituting another nutrient, statement A is false.
Step 3: Check statements B, C and D.
An essential element has to take part in the plant's metabolism (B), its absence must stop the plant from completing its life cycle (C), and only a small, fixed set of elements meet this bar (D). All three hold up.
Step 4: Combine the results.
B, C and D survive the check while A fails it.
Final answer: Option 4, B, C and D describe true essentiality criteria.