Answer:
The correct answer is option D, that is, binary fission.
Step-by-step explanation:
The organism mentioned in the given question is having a cell wall and DNA, however, no evidence of the nucleus is there, which signifies that the organism would be a prokaryotic species like an Archea or a bacteria. The characteristic of multiplication or proliferation showed by the organism is an essential feature of life.
This characteristic of multiplication is termed as reproduction, and as the organism is a prokaryotic species like bacteria or archaea, the mode of reproduction witnessed would be the binary fission. The binary fission refers to an asexual mode of reproduction, in which the body of the organism gets separated into two novel bodies, and in the process, the DNA, that is, the genetic material gets duplicated.