Final answer:
The Japanese evacuation instructions given by soldiers and police officers during World War II would ruin the lunch get-together, as it pertains to the forced displacement and internment of Japanese Americans, a historically significant and disruptive event.
Step-by-step explanation:
The lunch get-together described in the question is most likely ruined by soldiers and police officers giving the Japanese evacuation instructions, a scenario that echoes historical events during World War II where Japanese Americans were displaced from their homes and interned in relocation centers. This event would bring a sense of fear, uncertainty, and disruption to those affected, more so than the other options provided. Japanese internment during World War II, the targeting of ethnic minorities during crises like the Great Kanto Earthquake, and broader incidents of military and police intervention throughout history exhibit how such actions can lead to significant consequences for communities and individuals.