Final answer:
In situations of rapidly changing circumstances, the necessary strategic transition is from defensive to offensive.
Step-by-step explanation:
In situations where the situation rapidly changes, the strategic transition that may be necessary is defensive to offensive. This means shifting from a defensive mindset to actively taking offensive actions. For example, in battle, when faced with unexpected circumstances, a defensive strategy may be initially employed to protect oneself.
However, if the situation rapidly changes, it may be necessary to switch to an offensive strategy to actively engage the opponent and gain an advantage. By transitioning from a defensive to an offensive approach, individuals or organizations can adapt to the changing situation, seize opportunities, and gain control over the outcome.