While there are many other characteristics that are common to most living things, like being made of cells, requiring energy, responding to stimuli, and maintaining homeostasis, the ability to reproduce and pass on genetic information is the defining characteristic of life.

Here's why:

* Reproduction: This ensures the continuation of a species. Without the ability to reproduce, a species would eventually die out.

* Growth and Development: Living things increase in size and complexity over time, following a set pattern of development. This is essential for survival and carrying out life processes.

While viruses can reproduce, they lack the ability to grow and develop independently. They need a host cell to reproduce, which makes them different from living organisms.

Therefore, the combination of reproduction, growth, and development sets living things apart from non-living matter.