Viruses can have beneficial effects. For example, some kill more-complex microorganisms, some of which are deadly to humans. But viruses have such simple structures that replacing just a few of a beneficial virus' s several million atoms can make it deadly to humans. Clearly, since alterations of greater complexity than this are commonly produced by random mutations, any virus could easily become dangerous to humans. If the statements above are true, than each of the following statements could also be true EXCEPT: ['No virus that is deadly to organisms of greater complexity than itself is beneficial to humans.', 'Random mutation makes some deadly viruses beneficial to humans.', 'Some microorganisms that are more complex than viruses are beneficial to humans.', 'Some viruses that fail to kill other viruses that are deadly to humans are nevertheless beneficial to humans.']