The correct option is B Schizocoel
Schizocoely is a process by which some animal embryos develop. Schizocoely occurs when a coelom is formed by splitting the mesodermal embryonic tissue. Schizocoelous development is attributed to phyla: Mollusca, Annelida and Arthropoda.
Thus, the correct answer is the option (B), 'Schizocoel'.