Correct Answer - C
The cells having cloned genes of interest can be grown on a small scale in the laboratory. The cultures may be used for extracting and purifying the desired protein. The cells can also be multiplied n a continuous culture system where the used medium is passed out from one side and fresh medium is added from the other side to maintain the cells in their physiologically ost active log/exponential phase-rapid multiplication of the cells. This type of culturing method produces a larger biomass to get higher yields of desired protein.