Answer
Military deception was employed by Belisarius to successfully lift the siege of Ariminum. By convincing the Ostrogothic forces, led by King Vitiges, that a large relief army was approaching, Belisarius used a ruse to create panic and uncertainty within the besieging army. This deception caused Vitiges to abandon the siege and retreat, thereby achieving Belisarius' objective of lifting the siege of Ariminum.