The correct option is C Mules and worker bees
Reproduction refers to the production of progeny (young ones/daughter cells) possessing features more or less similar to those of parents. Reproduction is a characteristic feature of living organisms.
Many fungi multiply and reproduce through asexual spores. Planaria can be reproduced through fragmentation in which fragmented parts of the organism regenerates and becomes a new organism. Reproduction in Amoeba occurs through binary fission in which a single cell is divided into two similar daughter cells.
However, there are many organisms which do not reproduce. For example: Mules, worker bees, infertile human couples, etc. So, reproduction cannot be an all-inclusive defining characteristic of living organisms.