Listing out what a virus can and cannot do side by side settles this question without needing to compare it to bacteria or eukaryotic cells at all.
- Signs that point to "non-living": A virus particle sitting outside any host cell can be crystallised like a chemical compound, has no cytoplasm or organelles, and carries out no respiration, growth, or independent metabolism whatsoever.
- Signs that point to "living": The moment the same particle enters a suitable host cell, it takes control of that cell's enzymes and ribosomes to copy its own genetic material and build new virus particles, a hallmark of reproduction that only living things otherwise show.
- Why "prokaryotic" and "eukaryotic" don't apply: Both of these terms assume the presence of an actual cell, complete with a plasma membrane and internal cell machinery. A virus has neither, so it cannot be filed under either cell type.
- Why "only living" falls short: This ignores the inert, crystal-like state a virus is in for most of its existence outside a host, which is a distinctly non-living behaviour.
Because a virus genuinely switches between an inert, non-living state and an actively replicating, living-like state depending on whether it is inside a host cell, it is best described as showing both sets of properties.
The correct answer is Living and non-living.