One-celled organisms, such as bacteria, can reproduce very quickly using the process called budding binary fission cytokinesis duplication

The correct answer is binary fission.

It is the process by which prokaryotic cells produce new cells that are genetically similar to the parent cell. It is an asexual  kind of reproduction.

it occurs in  three main steps

1. DNA replication to make a set of two chromosomes.

2. Chromosome segregation where the two chromosomes separate.

3. Cytokinesis, a process in which a new plasma membrane begins to form in the center of the cell followed by the splitting of the cytoplasm into two, and two daughter cells are formed which are genetically similar to each other and to the parent cell. 

cell regulation is conducted by special proteins.