The correct option is D All of the above
Sexual reproduction in fungi involves three steps - plasmogamy, karyogamy and meiosis. It starts with the fusion of the protoplasm (plasmogamy) between two cells and results in a dikaryotic phase with two nuclei in a cell. This is followed by karyogamy where the two nuclei fuse together to form a diploid zygote. This, then undergoes meiosis to form four haploid spores.