The correct option is C Micro-organisms
The term "single cell protein" is used to describe proteins derived from cells or proteins extracted from various micro-organisms such as yeast, fungi, algae and bacteria.
They are mass produced from various carbon sources such as agricultural wastes and can be used as food sources for humans or animals.
The dried cells of micro-organisms or the whole organism is harvested and consumed. This is a rich protein source that can be used as a human food supplement and can also be used as animal feeds.