Why do viruses need living hosts, such as bacteria or eukaryote cells? A) The host cell is the source of food for the virus. B) Viruses depend on the host cells that they infect to reproduce. Eliminate C) Viruses lack cell structure and cannot survive without a host cell. D) Viruses depend on a host cell because they lack their own DNA or RNA.

The answer is B) Viruses depend on the host cells that they infect to reproduce. Viruses have their own genetic material. But, they miss cell machinery to produce proteins from their genetic material and to reproduce. Thus, after they infect the host cells, their genetic material incorporates into the cell hosts' genome and use hosts' cell machinery.