Answer: The algae will form multi cellular colonies.
Explanation:
The algae earlier used to be unicellular but after sometime for their benefit they clubbed together forming the multi cellular colonies.
The benefit of these colonies is that they can now protect themselves from the predator protists.
By performing same functions they can act as organ to protect themselves from the protists by releasing chemical.
The effect of chemicals released from a single cells is always more effective than single cell.
