Why are viral infections considered more difficult to eradicate than bacterial infections?

The correct choice highlights that viruses replicate exclusively within host cells, which presents a significant challenge for treatment and eradication. This intracellular replication means that antiviral strategies must target the virus without damaging the host's own cells, making it difficult to find effective treatments that can clear the virus without causing harm to the patient.

In contrast, bacterial infections can often be treated effectively with antibiotics that specifically target bacterial structures or functions not present in human cells, allowing for a clearer path to eradication.

The other options do not accurately represent the complexities involved in viral infection treatment. Not all viruses are resistant to all forms of treatment; some viruses can be effectively managed with antiviral medications. Additionally, while bacteria can mutate, it is not necessarily the case that they have faster mutation rates than viruses, which frequently undergo rapid changes. Moreover, not all viral infections are recurrent, and many can be resolved with proper treatment, further illustrating the nuances in managing these types of infections.