 What object is found by the guards, giving away the six Venusian conspirators? Who does it belong to?
"They had to acclimate themselves to Venus's climate. The native guard of honor, posted a hundred yards from the Earth-ship, stood stolidly at attention with their old-fashioned proton-rifles slung over their backs. They think there will be hordes of immigrants from Earth, now that we know Venus is habitable. And there's some sort of a paltry underground group that is spreading the word that the immigrants will drive the native Venusians—the descendants of the first expedition, that is—right down into the mud. We have agreed that, if the Earth-ship returns, it means disaster for Venus. Therefore, it must not return."
 A rifle. It belongs to the guard they killed just before breaking into where the Earth ship is kept.
 A spy ray. It belongs to the six insurgents who plan to blow up the Earth ship.  A Venus-tobacco cigarette. It belongs to the Exec officer, who the six insurgents killed when breaking into the Earth ship.  An atomite bomb. It belongs to the guard they killed just before breaking into where the Earth ship is kept.  A rifle. It belongs to the guard they killed just before breaking into where the Earth ship is kept.