Deficiency of mineral nutrition does not cause which of these

The correct option is Etiolation.

To understand why etiolation is not caused by the deficiency of mineral nutrients, let us break down each of the options and their causes:
1. Chlorosis: This is the loss of chlorophyll leading to the yellowing of leaves. It is a common symptom caused by the deficiency of essential mineral nutrients such as nitrogen (N), potassium (K), magnesium (Mg), sulfur (S), iron (Fe), manganese (Mn), zinc (Zn), and molybdenum (Mo).
2. Necrosis: This refers to the localized death of plant tissues, particularly leaves. It is caused by the deficiency of minerals like calcium (Ca), magnesium (Mg), copper (Cu), and potassium (K).
3. Shortening of internodes: The inhibition of cell division and reduction in growth lead to shortened internodes, which is a symptom of the deficiency of minerals like nitrogen (N), sulfur (S), and molybdenum (Mo).
4. Etiolation: Etiolation is a developmental state in plants grown in complete or partial absence of light. It is characterized by pale, weak stems, longer internodes (due to lack of light stimulus), and small, yellow leaves. Unlike the other options, etiolation is a physiological response directly caused by the lack of light (shading/darkness), not by a deficiency of minerals in the soil.

Therefore, etiolation is the only condition among the choices that is not caused by mineral nutrient deficiency.