What is the process by which a single parent reproduces without the involvement of another organism?

Asexual reproduction is the process by which a single parent organism produces offspring without the involvement of genetic contributions from another organism. This method allows for the offspring to be genetically identical to the parent, barring any mutations. Common forms of asexual reproduction include binary fission, budding, and vegetative reproduction.

In essence, asexual reproduction enables organisms to rapidly increase their population in stable environments, as it does not require a partner for reproduction. This strategy is especially advantageous for simple organisms like bacteria, which often reproduce through processes like binary fission—a specific type of asexual reproduction where one cell divides to form two identical cells.

Other terms listed, such as sexual reproduction and fertilisation, inherently involve two parents and the combination of genetic material from both, which differentiates them from asexual reproduction. Thus, the correct choice clearly describes the concept of reproduction by a single parent without a partner's involvement.