Answer: Option C " S. cerevisiae"
Explanation: Saccharomyces cerevisiae can be used as a model system for the fundamental cellular process related to eukaryotic organism.
The reason it is being used for the study of eukaryotic cells is as follows:
1- It has high multiplication rate.
2- As per the study, more than 60% of the functional gene is known.
3- 30% of the human genes has the same homology to this yeast
Hence, S. cerevisiae is used as a model organism for studying eukaryotic cells.