The correct option is
B Gametic meiosis
During unfavourable conditions, the vegetative cells of haploid protists become encysted with resistant outer covering in which cell metabolism is more or less completely shut down. It provides resistance to desiccation. These dormant structures resume metabolic activity and germinate asexually to form new organism upon arrival of favourable growth conditions. For example, some chrysophytes.
Binary fission is also asexual mode of reproduction in protists wherein replication of chromosome is followed by inward growth of cytoplasmic membrane and the cell wall splitting from the outside toward the centre to divide the cell into two daughter cells.
Gametic meiosis refers to meiosis in diploid gamete mother cells to produce haploid gametes which will then fuse to restore the vegetative diploid phase. Therefore, it occurs in diploid protists. For example, diatoms, metazoans.
Zygotic meiosis occurs directly after fertilization, resulting in production of all haploid individuals, the diploid phase is represented by zygote only while the vegetative phase is haploid. For example, sporozoans and dinoflagellates.
Therefore, the correct answer is option D.