Critical elements are elements necessary for the successful growth and development of a species but they are always deficient in soil. They are namely Nitrogen(N) , Phosphorus(P) and Potassium(K).

The deficiency can either be because of leaching or because of absorption by plants .

In agriculture, leaching is the loss of water-soluble plant nutrients from the soil, due to rain and irrigation.

Example:- Red and yellow soil is formed due to leaching.

If plants will absorb the nutrients from the soil, then the soil will definitely become deficient of those elements.

So, the correct answer will be N, P, K.

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