Suggest a hypothesis under what circumstances it is preferable for multicellular algae to reproduce by spores rather than by scraps of thallus.

When multiplying by spores, many descendants are formed. This happens when the likelihood of algae spreading is small (there are no free places for settling nearby).

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.