Correct Answer – C
Macrocyst formation is a product of sexual reproduction of slime moulds. During formation of macrocyte a myxamoeba grows in size and function as a female gamete. It attracts a number of male gametes, But, only one male gamete fuses with the female gamete.
The fusion product is known as zygote. The zygote secretes a thick wall covering and is called macrocyst. The two nuclei fuse in the macrocyst forming single diploid nucleus.