The technique of growing plants in nutrient solution, in

Solution

(A) Identification of essentiality of mineral elements: Hydroponics allows for precise control over the nutrient environment, making it ideal for studying the essentiality of minerals. (B) Commercial production of vegetables: Hydroponics is widely used for the commercial production of vegetables in controlled environments, enhancing yield and quality. (C) Studying the deficiency symptoms of a particular element: Hydroponics is perfect for controlled studies on nutrient deficiencies, as it can isolate variables effectively. (D) Conservation of germplasm: This is generally not done via hydroponics but through cryopreservation or seed banks.