<Li> Caligula, son of Germanicus (natural) </Li> <Li> Drusus, stepson of Augustus (by marriage) <Ul> <Li> Claudius, son of Drusus (natural) <Ul> <Li> Nero, son of Claudius (by adoption) </Li> </Ul> </Li> </Ul> </Li> <Ul> <Li> Claudius, son of Drusus (natural) <Ul> <Li> Nero, son of Claudius (by adoption) </Li> </Ul> </Li> </Ul> <Li> Claudius, son of Drusus (natural) <Ul> <Li> Nero, son of Claudius (by adoption) </Li> </Ul> </Li>

Which of the following is not true of the military during the julio-claudian period