Your grandfather often reminds you that "prevention is the best medicine." if that is his attitude toward health, which of the following would you expect him to do? a. maintain brushing his teeth and not flossing because he has had few dental problems b. go to the doctor regularly because he can monitor his health before problems get severe c. limit his calorie intake because he wants to look good as he ages d. limit his cigars because he feels enjoyment is as equally important as his health

Viruses use the host's machinery to make copies of themselves. however, some human viruses require a type of replication that humans do not normally have. for example, humans normally do not have the ability to convert rna into dna. how can these types of viruses infect humans, when human cells cannot perform a particular role that the virus requires? a) the virus causes mutations in the human cells, resulting in the formation of new enzymes that are capable of performing these roles.b) the viral genome codes for specialized enzymes not in the host.c) the virus infects only those cells and species that can perform all the replication roles necessary.d) viruses can stay in a quiescent state until the host cell evolves this ability.