(a) The alga X is likely to be Spirogyra.
(b) The alga is green in colour.
(c) This mode of forming new alga from the breaking-up of the parent alga is termed as fragmentation.
(d) The splitting of Amoeba is termed as fission, which occurs only in unicellular organisms. The splitting of alga is termed as fragmentation, which occurs only in multicellular organisms.
(e) Sea anemone reproduces in the same way as the alga X.