A fermenter is used to produce penicillin. Why is it necessary to keep stirring continuously during fermentation?
- Ato keep the $\textit{Penicillium}$ in contact with fresh oxygen and nutrients
- Bto move the $\textit{Penicillium}$ to the bottom of the fermenter
- Cto move the $\textit{Penicillium}$ to the top of the fermenter
- Dto stop the $\textit{Penicillium}$ reacting with the wall of the fermenter