Question

Hydroponics is a method of cultivation of plants without the use of
A. Water
B. Air
C. Soil
D. Sunlight

Answer 1

Hint:
Plants are autotrophs that use the process of photosynthesis for the production of food. During the process of photosynthesis, they transform light energy into chemical energy in the presence of sunlight and chlorophyll. The essential nutrients and water that are required come from the soil. Hydroponics is the method of cultivation in which plants are grown in a nutrient-rich solution.

Complete answer:
Hydroponics is an agricultural method where plants, generally crops are cultivated in a nutrient medium in the complete absence of soil. The sterile mediums used in hydroponics are rockwool, sand gravel, clay pellets, perlite, etc which gives stability to roots. Different nutrients are passed through roots based on the hydroponics system used. Other essential things required for photosynthesis such as oxygen and light are provided to the plants. The pH is also regulated. Artificial lighting is provided in the areas where natural sunlight is absent. The different hydroponics systems are:- Ebb and flow systems, nutrient film technique, drop systems, wick systems, aeroponics, deep water culture, etc. In a hydroponic setup, the materials required include a reservoir that holds the nutrient solution, grow tray to hold the plants, a growing medium in which the plant grows, and a nutrient solution which is the nutrients dissolved in water required for photosynthesis.
Thus, the correct answer is:- Soil.

Option ‘C’ is correct

Note:
Hydroponics is of great commercial use as many plants can be cultivated at the same time as compared to the plants grown using soil. The plants also grow faster which results in a high yield. The water and nutrients used can be reused and recycled. The quality of food will be good and organic as fertilizers and pesticides are not used.