Binary fission. This is because chlamydomonas is a unicellular algae
It is binary fission, also named as prokaryotic fission. It is a single cell (unicellular) organism which is simple and does not have complex structure. Under favourable condition, chlamydomonas undergoes division of its protoplasm to up to 16 daughter protoplasts which will then mature followed by the formation of their own cell wall and flagella. These daughter cells are called zoospores, and are kept within the cell wall of the parent cell. Then it will be ruptured and releases the daughter cells to become new daughter chlamydomonas.