In principle, viruses are considered as non living because they don't fulfill all eight characteristics of living organisms, i.e. RAREHOGG (reproduction, adaptation, response to stimuli, energy production, homeostasis, organization of cells, growth and development, and genetics). Specifically, they don't have energy metabolism, they don't grow, they don't respond to stimuli. However, they can adapt the environment and reproduce. But they do not reproduce independently, rather they need a host cell and use its machinery for reproduction. Based on these reasons, they are considered as living organisms.
Adaptation, Genetic material, Reproduce
Those characteristics are cellular organization, reproduction, metabolism, homeostasis, heredity, response to stimuli, growth and development, and adaptation through evolution.
D.Reproduce, have Genetic Material (Nucleic Acids) and Adapt
The statements A, B and C are incorrect because viruses are not made of cells, they just carry the genetic material to exploit the cell machinery for its replication in the host, it is for that reason that viruses are considered parasitic
Reproduce, have Genetic Material (Nucleic Acids) and Adapt
The only living characteristic of viruses are that they reproduce but only inside the host body, using its machinery they can mutate and change over time. In the case of retroviruses, DNA can be passed to succeeding generations.
the non living characteristics of viruses include that they are not cells; they lack plasma membrane, cytoplasm and cellular organelles and they can not undergo metabolism. they can not maintain homeostasis as they crystallize out of the host body. they can not grow, just multiply using the host machinery.
considering some facts that viruses can reproduce inside hosts body, and that they can mutate we can say that they are living.
but flipping the coin, viruses are not cells, they lack cytoplasm and organelles and they crystallize out of the host body. We can say that they are non-living.
but up till now biologists place viruses on a border line of living and non living.