Direction: Read the following passages carefully and answer the question that follows.
In presents scenario of increasing demand for cut flowers, protected cultivation in green house is the best alternatives for using land and other resources more efficiently. In protected environment, suitable environmental conditions for optimum plant growth are provided ultimately quality with products. Greenhouse is made up of glass or plastic film, which allows the solar radiations to pass through but traps the thermal radiations emitted by plants inside and, thereby, provide inside, On the basis of material used, building cost and technology used, green house can be of three types: low-cost greenhouse, medium-cost greenhouse and hi-tech greenhouse.