<Li> Civil war is a war between forces belonging to the same nation or political entity . </Li> <Li> Conventional warfare is declared war between states in which nuclear, biological, or chemical weapons are not used or see limited deployment . </Li> <Li> Cyberwarfare involves the actions by a nation - state or international organization to attack and attempt to damage another nation's information systems . </Li> <Li> Insurgency is a rebellion against authority, when those taking part in the rebellion are not recognized as belligerents (lawful combatants). An insurgency can be fought via counter-insurgency warfare, and may also be opposed by measures to protect the population, and by political and economic actions of various kinds aimed at undermining the insurgents' claims against the incumbent regime . </Li>

Which of the following may have been the cause of world war ii