The correct option is C Haplodiplontic, Diplontic
In haplo-diplontic life cycle, diploid sporophytic body alternates with multicellular, saprophytic/autotrophic, independent haploid gametophyte. Both the phases are equally prevalent during the liife cycle.
In diplontic life cycle, diploid sporophytic body is predominant and alternates with a very short haploid gametophytic phase.
While most algal genera are haplontic, some of them like Ectocarpus are haplo-diplontic and Fucus is diplontic.